# @ohos.net.policy (Network Policy Management)

The **policy** module provides APIs for managing network policies, through which you can control and manage the data volume used.

> **NOTE**
>
> The initial APIs of this module are supported since API version 10. Newly added APIs will be marked with a superscript to indicate their earliest API version.

## Modules to Import

```js
import policy from '@ohos.net.policy'
```

## policy.setBackgroundAllowed<sup>10+</sup>

setBackgroundAllowed(isAllowed: boolean, callback: AsyncCallback\<void>): void

Specifies whether background applications are allowed to access the network. This API uses an asynchronous callback to return the result.

**System API**: This is a system API.

**Required permission**: ohos.permission.MANAGE_NET_STRATEGY

**System capability**: SystemCapability.Communication.NetManager.Core

**Parameters**

| Name  | Type                                   | Mandatory| Description      |
| -------- | --------------------------------------- | ---- | ---------- |
| isAllowed | boolean | Yes  | Whether background applications are allowed to use mobile data.|
| callback | AsyncCallback\<void> | Yes  | Callback used to return the result. If the operation is successful, **err** is **undefined**. Otherwise, **err** is an error object.|

**Error codes**

| ID| Error Message                                     |
| ------- | -------------------------------------------- |
| 201     | Permission denied.                           |
| 202     | Non-system applications use system APIs.     |
| 401     | Parameter error.                             |
| 2100001 | Invalid parameter value.                |
| 2100002 | Operation failed. Cannot connect to service.|
| 2100003 | System internal error.                  |

**Example**

```js
policy.setBackgroundAllowed(true, (error) => {
  console.log(JSON.stringify(error))
})
;
```

## policy.setBackgroundAllowed<sup>10+</sup>

setBackgroundAllowed(isAllowed: boolean): Promise\<void>

Specifies whether background applications are allowed to access the network. This API uses a promise to return the result.

**System API**: This is a system API.

**Required permission**: ohos.permission.MANAGE_NET_STRATEGY

**System capability**: SystemCapability.Communication.NetManager.Core

**Parameters**

| Name  | Type                                   | Mandatory| Description      |
| -------- | --------------------------------------- | ---- | ---------- |
| isAllowed | boolean | Yes  | Whether background applications are allowed to use mobile data.|

**Error codes**

| ID| Error Message                                     |
| ------- | -------------------------------------------- |
| 201     | Permission denied.                           |
| 202     | Non-system applications use system APIs.     |
| 401     | Parameter error.                             |
| 2100001 | Invalid parameter value.                     |
| 2100002 | Operation failed. Cannot connect to service.|
| 2100003 | System internal error.                  |

**Return value**

| Type                             | Description                                 |
| --------------------------------- | ------------------------------------- |
| Promise\<void> | Promise used to return the result. If the operation is successful, no value is returned. If the operation fails, an error message is returned.|

**Example**

```js
policy.setBackgroundAllowed(true).then(function (error) {
  console.log(JSON.stringify(error))
})
```

## policy.isBackgroundAllowed<sup>10+</sup>

isBackgroundAllowed(callback: AsyncCallback\<boolean>): void

Checks whether the current application is allowed to access the network when running at the background. This API uses an asynchronous callback to return the result.

**System API**: This is a system API.

**Required permission**: ohos.permission.MANAGE_NET_STRATEGY

**System capability**: SystemCapability.Communication.NetManager.Core

**Parameters**

| Name  | Type                                   | Mandatory| Description      |
| -------- | --------------------------------------- | ---- | ---------- |
| callback | AsyncCallback\<boolean> | Yes  | Callback used to return the result. If the operation is successful, the value **true** is returned, which means that background applications are allowed to use mobile data. If the operation fails, an error message is returned.|

**Error codes**

| ID| Error Message                                     |
| ------- | -------------------------------------------- |
| 201     | Permission denied.                           |
| 202     | Non-system applications use system APIs.     |
| 401     | Parameter error.                             |
| 2100001 | Invalid parameter value.                     |
| 2100002 | Operation failed. Cannot connect to service.|
| 2100003 | System internal error.                  |

**Example**

```js
policy.isBackgroundAllowed((error, data) => {
  console.log(JSON.stringify(error))
  console.log(JSON.stringify(data))
});
```

## policy.isBackgroundAllowed<sup>10+</sup>

isBackgroundAllowed(): Promise\<boolean>;

Checks whether the current application is allowed to access the network when running at the background. This API uses a promise to return the result.

**System API**: This is a system API.

**Required permission**: ohos.permission.MANAGE_NET_STRATEGY

**System capability**: SystemCapability.Communication.NetManager.Core

**Return value**

| Type                             | Description                                 |
| --------------------------------- | ------------------------------------- |
| Promise\<boolean> | Promise used to return the result. If the operation is successful, the value **true** is returned, which means that background applications are allowed to use mobile data. If the operation fails, an error message is returned.|

**Error codes**

| ID| Error Message                                     |
| ------- | -------------------------------------------- |
| 201     | Permission denied.                           |
| 202     | Non-system applications use system APIs.     |
| 401     | Parameter error.                             |
| 2100001 | Invalid parameter value.                     |
| 2100002 | Operation failed. Cannot connect to service.|
| 2100003 | System internal error.                  |

**Example**

```js
policy.isBackgroundAllowed().then(function (error, data) {
  console.log(JSON.stringify(error))
  console.log(JSON.stringify(data))
})
```

## policy.setPolicyByUid<sup>10+</sup>

setPolicyByUid(uid: number, policy: NetUidPolicy, callback: AsyncCallback\<void>): void

Sets the metered network access policy for the application specified by a given UID. This API uses an asynchronous callback to return the result.

**System API**: This is a system API.

**Required permission**: ohos.permission.MANAGE_NET_STRATEGY

**System capability**: SystemCapability.Communication.NetManager.Core

**Parameters**

| Name  | Type                                   | Mandatory| Description      |
| -------- | --------------------------------------- | ---- | ---------- |
| uid | number | Yes  | Unique ID of the application.|
| policy | [NetUidPolicy](#netuidpolicy10) | Yes| Network access policy for the application.|netuidpolicy
| callback | AsyncCallback\<void> | Yes  | Callback used to return the result. If the operation is successful, no value is returned. If the operation fails, an error message is returned.|

**Error codes**

| ID| Error Message                                     |
| ------- | -------------------------------------------- |
| 201     | Permission denied.                           |
| 202     | Non-system applications use system APIs.     |
| 401     | Parameter error.                             |
| 2100001 | Invalid parameter value.                     |
| 2100002 | Operation failed. Cannot connect to service.|
| 2100003 | System internal error.                  |

**Example**

```js
policy.setPolicyByUid(11111, policy.NetUidPolicy.NET_POLICY_NONE, (error) => {
   console.log(JSON.stringify(error))
});
```

## policy.setPolicyByUid<sup>10+</sup>

setPolicyByUid(uid: number, policy: NetUidPolicy): Promise\<void>;

Sets the metered network access policy for the application specified by a given UID. This API uses a promise to return the result.

**System API**: This is a system API.

**Required permission**: ohos.permission.MANAGE_NET_STRATEGY

**System capability**: SystemCapability.Communication.NetManager.Core

**Parameters**

| Name  | Type                                   | Mandatory| Description      |
| -------- | --------------------------------------- | ---- | ---------- |
| uid | number | Yes  | Unique ID of the application.|
| policy | [NetUidPolicy](#netuidpolicy10) | Yes| Network access policy for the application.|

**Return value**

| Type                             | Description                                 |
| --------------------------------- | ------------------------------------- |
| Promise\<void> | Promise used to return the result. If the operation is successful, no value is returned. If the operation fails, an error message is returned.|

**Error codes**

| ID| Error Message                                     |
| ------- | -------------------------------------------- |
| 201     | Permission denied.                           |
| 202     | Non-system applications use system APIs.     |
| 401     | Parameter error.                             |
| 2100001 | Invalid parameter value.                     |
| 2100002 | Operation failed. Cannot connect to service.|
| 2100003 | System internal error.                  |

**Example**

```js
policy.setPolicyByUid(11111, policy.NetUidPolicy.NET_POLICY_NONE).then(function (error) {
  console.log(JSON.stringify(error))
})
```

## policy.getPolicyByUid<sup>10+</sup>

getPolicyByUid(uid: number, callback: AsyncCallback\<NetUidPolicy>): void

Obtains the network access policy for the application specified by a given UID. This API uses an asynchronous callback to return the result.

**System API**: This is a system API.

**Required permission**: ohos.permission.MANAGE_NET_STRATEGY

**System capability**: SystemCapability.Communication.NetManager.Core

**Parameters**

| Name  | Type                                   | Mandatory| Description      |
| -------- | --------------------------------------- | ---- | ---------- |
| uid | number | Yes| Unique ID of the application.|
| callback | AsyncCallback\<[NetUidPolicy](#netuidpolicy10)> | Yes  | Callback used to return the result. If the operation is successful, the operation result is returned. If the operation fails, an error message is returned.|
**Error codes**

| ID| Error Message                                     |
| ------- | -------------------------------------------- |
| 201     | Permission denied.                           |
| 202     | Non-system applications use system APIs.     |
| 401     | Parameter error.                             |
| 2100001 | Invalid parameter value.                     |
| 2100002 | Operation failed. Cannot connect to service.|
| 2100003 | System internal error.                  |

**Example**

```js
policy.getPolicyByUid(11111, (error, data) => {
  console.log(JSON.stringify(error))
  console.log(JSON.stringify(data))
});
```

## policy.getPolicyByUid<sup>10+</sup>

getPolicyByUid(uid: number): Promise\<NetUidPolicy>;

Obtains the network access policy for the application specified by a given UID. This API uses a promise to return the result.

**System API**: This is a system API.

**Required permission**: ohos.permission.MANAGE_NET_STRATEGY

**System capability**: SystemCapability.Communication.NetManager.Core

**Parameters**

| Name  | Type                                   | Mandatory| Description      |
| -------- | --------------------------------------- | ---- | ---------- |
| uid | number | Yes| Unique ID of the application.|

**Return value**

| Type                             | Description                                 |
| --------------------------------- | ------------------------------------- |
| Promise\<[NetUidPolicy](#netuidpolicy10)> | Promise used to return the result. If the operation is successful, the operation result is returned. If the operation fails, an error message is returned.|

**Error codes**

| ID| Error Message                                     |
| ------- | -------------------------------------------- |
| 201     | Permission denied.                           |
| 202     | Non-system applications use system APIs.     |
| 401     | Parameter error.                             |
| 2100001 | Invalid parameter value.                     |
| 2100002 | Operation failed. Cannot connect to service.|
| 2100003 | System internal error.                  |                |

**Example**

```js
policy.getPolicyByUid(11111).then(function (error, data) {
  console.log(JSON.stringify(error))
  console.log(JSON.stringify(data))
})
```

## policy.getUidsByPolicy<sup>10+</sup>

getUidsByPolicy(policy: NetUidPolicy, callback: AsyncCallback\<Array\<number>>): void

Obtains all UIDs that match the specified network policy. This API uses an asynchronous callback to return the result.

**System API**: This is a system API.

**Required permission**: ohos.permission.MANAGE_NET_STRATEGY

**System capability**: SystemCapability.Communication.NetManager.Core

**Parameters**

| Name  | Type                                   | Mandatory| Description      |
| -------- | --------------------------------------- | ---- | ---------- |
| policy | [NetUidPolicy](#netuidpolicy10) | Yes| Network policy for the application.|
| callback | AsyncCallback\<Array\<number>> | Yes  | Callback used to return the result. If the operation is successful, the operation result is returned. If the operation fails, an error message is returned.|

**Error codes**

| ID| Error Message                                     |
| ------- | -------------------------------------------- |
| 201     | Permission denied.                           |
| 202     | Non-system applications use system APIs.     |
| 401     | Parameter error.                             |
| 2100001 | Invalid parameter value.                     |
| 2100002 | Operation failed. Cannot connect to service.|
| 2100003 | System internal error.                  |

**Example**

```js
policy.getUidsByPolicy(11111, (error, data) => {
  console.log(JSON.stringify(error))
  console.log(JSON.stringify(data))
});
```

## policy.getUidsByPolicy<sup>10+</sup>

getUidsByPolicy(policy: NetUidPolicy): Promise\<Array\<number>>;

Obtains all UIDs that match the specified network policy. This API uses a promise to return the result.

**System API**: This is a system API.

**Required permission**: ohos.permission.MANAGE_NET_STRATEGY

**System capability**: SystemCapability.Communication.NetManager.Core

**Parameters**

| Name  | Type                                   | Mandatory| Description      |
| -------- | --------------------------------------- | ---- | ---------- |
| policy | [NetUidPolicy](#netuidpolicy10) | Yes| Network policy for the application.|

**Return value**

| Type                             | Description                                 |
| --------------------------------- | ------------------------------------- |
| Promise\<Array\<number>> | Promise used to return the result. If the operation is successful, the operation result is returned. If the operation fails, an error message is returned.|

**Error codes**

| ID| Error Message                                     |
| ------- | -------------------------------------------- |
| 201     | Permission denied.                           |
| 202     | Non-system applications use system APIs.     |
| 401     | Parameter error.                             |
| 2100001 | Invalid parameter value.                     |
| 2100002 | Operation failed. Cannot connect to service.|
| 2100003 | System internal error.                  |

**Example**

```js
policy.getUidsByPolicy(11111).then(function (error, data) {
  console.log(JSON.stringify(error))
  console.log(JSON.stringify(data))
})
```

## policy.getNetQuotaPolicies<sup>10+</sup>

getNetQuotaPolicies(callback: AsyncCallback\<Array\<NetQuotaPolicy>>): void

Obtains the network quota policies. This API uses an asynchronous callback to return the result.

**System API**: This is a system API.

**Required permission**: ohos.permission.MANAGE_NET_STRATEGY

**System capability**: SystemCapability.Communication.NetManager.Core

**Parameters**

| Name  | Type                                   | Mandatory| Description      |
| -------- | --------------------------------------- | ---- | ---------- |
| callback | AsyncCallback\<Array\<[NetQuotaPolicy](#netquotapolicy10)>> | Yes  | Callback used to return the result.|

**Error codes**

| ID| Error Message                                     |
| ------- | -------------------------------------------- |
| 201     | Permission denied.                           |
| 202     | Non-system applications use system APIs.     |
| 401     | Parameter error.                             |
| 2100001 | Invalid parameter value.                     |
| 2100002 | Operation failed. Cannot connect to service.|
| 2100003 | System internal error.                  |

**Example**

```js
policy.getNetQuotaPolicies((error, data) => {
  console.log(JSON.stringify(error))
  console.log(JSON.stringify(data))
});
```

## policy.getNetQuotaPolicies<sup>10+</sup>

getNetQuotaPolicies(): Promise\<Array\<NetQuotaPolicy>>;

Obtains the network quota policies. This API uses a promise to return the result.

**System API**: This is a system API.

**Required permission**: ohos.permission.MANAGE_NET_STRATEGY

**System capability**: SystemCapability.Communication.NetManager.Core

**Return value**

| Type                             | Description                                 |
| --------------------------------- | ------------------------------------- |
| Promise\<Array\<[NetQuotaPolicy](#netquotapolicy10)>> | Promise used to return the result.|

**Error codes**

| ID| Error Message                                     |
| ------- | -------------------------------------------- |
| 201     | Permission denied.                           |
| 202     | Non-system applications use system APIs.     |
| 401     | Parameter error.                             |
| 2100002 | Operation failed. Cannot connect to service.|
| 2100003 | System internal error.                  |

**Example**

```js
policy.getNetQuotaPolicies().then(function (error, data) {
  console.log(JSON.stringify(error))
  console.log(JSON.stringify(data))
})

```

## policy.setNetQuotaPolicies<sup>10+</sup>

setNetQuotaPolicies(quotaPolicies: Array\<NetQuotaPolicy>, callback: AsyncCallback\<void>): void

Sets network quota policies. This API uses an asynchronous callback to return the result.

**System API**: This is a system API.

**Required permission**: ohos.permission.MANAGE_NET_STRATEGY

**System capability**: SystemCapability.Communication.NetManager.Core

**Parameters**

| Name  | Type                                   | Mandatory| Description      |
| -------- | --------------------------------------- | ---- | ---------- |
| quotaPolicies | Array\<[NetQuotaPolicy](#netquotapolicy10)> | Yes| Network quota policies.|
| callback | AsyncCallback\<void> | Yes  | Callback used to return the result. If the operation is successful, no value is returned. If the operation fails, an error message is returned.|

**Error codes**

| ID| Error Message                                     |
| ------- | -------------------------------------------- |
| 201     | Permission denied.                           |
| 202     | Non-system applications use system APIs.     |
| 401     | Parameter error.                             |
| 2100001 | Invalid parameter value.                     |
| 2100002 | Operation failed. Cannot connect to service.|
| 2100003 | System internal error.                  |

**Example**

```js
import connection from '@ohos.net.connection';

let netQuotaPolicyList = []
let netquotapolicy = {
  networkMatchRule: {
    netType: connection.NetBearType.BEARER_CELLULAR,
    identity:"",
    simId:"1"
  },
  quotaPolicy: {
    periodDuration: "M1",
    warningBytes: 40000,
    limitBytes: 50000,
    metered: true,
    limitAction: policy.LimitAction.LIMIT_ACTION_NONE
  },
}

netQuotaPolicyList.push(netquotapolicy);

policy.setNetQuotaPolicies(netQuotaPolicyList, (error) => {
  console.log(JSON.stringify(error))
});
```

## policy.setNetQuotaPolicies<sup>10+</sup>

setNetQuotaPolicies(quotaPolicies: Array\<NetQuotaPolicy>): Promise\<void>;

Sets network quota policies. This API uses a promise to return the result.

**System API**: This is a system API.

**Required permission**: ohos.permission.MANAGE_NET_STRATEGY

**System capability**: SystemCapability.Communication.NetManager.Core

**Parameters**

| Name  | Type                                   | Mandatory| Description      |
| -------- | --------------------------------------- | ---- | ---------- |
| quotaPolicies | Array\<[NetQuotaPolicy](#netquotapolicy10)> | Yes| Network quota policies.|

**Error codes**

| ID| Error Message                                     |
| ------- | -------------------------------------------- |
| 201     | Permission denied.                           |
| 202     | Non-system applications use system APIs.     |
| 401     | Parameter error.                             |
| 2100001 | Invalid parameter value.                     |
| 2100002 | Operation failed. Cannot connect to service.|
| 2100003 | System internal error.                  |
**Return value**

| Type                             | Description                                 |
| --------------------------------- | ------------------------------------- |
| Promise\<void> | Promise used to return the result. If the operation is successful, no value is returned. If the operation fails, an error message is returned.|
**Example**

```js
import connection from '@ohos.net.connection';

let netQuotaPolicyList = []
let netquotapolicy = {
  networkMatchRule: {
    netType: connection.NetBearType.BEARER_CELLULAR,
    identity:"",
    simId:"1"
  },
  quotaPolicy: {
    periodDuration: "M1",
    warningBytes: 40000,
    limitBytes: 50000,
    metered: true,
    limitAction: policy.LimitAction.LIMIT_ACTION_NONE
  },
}

netQuotaPolicyList.push(netquotapolicy);

policy.setNetQuotaPolicies(netQuotaPolicyList).then(function (error) {
  console.log(JSON.stringify(error))
})
```

## policy.isUidNetAllowed<sup>10+</sup>

isUidNetAllowed(uid: number, isMetered: boolean, callback: AsyncCallback\<boolean>): void

Checks whether the application specified by a given UID is allowed to access a metered network. This API uses an asynchronous callback to return the result.

**System API**: This is a system API.

**Required permission**: ohos.permission.MANAGE_NET_STRATEGY

**System capability**: SystemCapability.Communication.NetManager.Core

**Parameters**

| Name  | Type                                   | Mandatory| Description      |
| -------- | --------------------------------------- | ---- | ---------- |
| uid | number | Yes| Unique ID of the application.|
| isMetered | boolean | Yes| Whether the network is a metered network.|
| callback | AsyncCallback\<boolean> | Yes  | Callback used to return the result. The value **true** means that the application is allowed to access metered networks, and **false** means the opposite.|

**Error codes**

| ID| Error Message                                     |
| ------- | -------------------------------------------- |
| 201     | Permission denied.                           |
| 202     | Non-system applications use system APIs.     |
| 401     | Parameter error.                             |
| 2100001 | Invalid parameter value.                     |
| 2100002 | Operation failed. Cannot connect to service.|
| 2100003 | System internal error.                  |

**Example**

```js
policy.isUidNetAllowed(11111, true, (error, data) => {
  console.log(JSON.stringify(error))
  console.log(JSON.stringify(data))
});
```

## policy.isUidNetAllowed<sup>10+</sup>

isUidNetAllowed(uid: number, isMetered: boolean): Promise\<boolean>;

Checks whether the application specified by a given UID is allowed to access a metered network. This API uses a promise to return the result.

**System API**: This is a system API.

**Required permission**: ohos.permission.MANAGE_NET_STRATEGY

**System capability**: SystemCapability.Communication.NetManager.Core

**Parameters**

| Name  | Type                                   | Mandatory| Description      |
| -------- | --------------------------------------- | ---- | ---------- |
| uid | number | Yes| Unique ID of the application.|
| isMetered | boolean | Yes| Whether the network is a metered network.|

**Return value**

| Type                             | Description                                 |
| --------------------------------- | ------------------------------------- |
| Promise\<boolean> | Promise used to return the result.|

**Error codes**

| ID| Error Message                                     |
| ------- | -------------------------------------------- |
| 201     | Permission denied.                           |
| 202     | Non-system applications use system APIs.     |
| 401     | Parameter error.                             |
| 2100001 | Invalid parameter value.                     |
| 2100002 | Operation failed. Cannot connect to service.|
| 2100003 | System internal error.                  |

**Example**

```js
policy.isUidNetAllowed(11111, true).then(function (error, data) {
  console.log(JSON.stringify(error))
  console.log(JSON.stringify(data))
})
```

## policy.isUidNetAllowed<sup>10+</sup>

isUidNetAllowed(uid: number, iface: string, callback: AsyncCallback\<boolean>): void

Checks whether the application specified by a given UID is allowed to access the network specified by a given **iface**. This API uses an asynchronous callback to return the result.

**System API**: This is a system API.

**Required permission**: ohos.permission.MANAGE_NET_STRATEGY

**System capability**: SystemCapability.Communication.NetManager.Core

**Parameters**

| Name  | Type                                   | Mandatory| Description      |
| -------- | --------------------------------------- | ---- | ---------- |
| uid | number | Yes| Unique ID of the application.|
| iface | string | Yes| Name of the target network.|
| callback | AsyncCallback\<boolean> | Yes  | Callback used to return the result. The value **true** means that the application is allowed to access the specified network, and **false** means the opposite.|

**Error codes**

| ID| Error Message                                     |
| ------- | -------------------------------------------- |
| 201     | Permission denied.                           |
| 202     | Non-system applications use system APIs.     |
| 401     | Parameter error.                             |
| 2100001 | Invalid parameter value.                     |
| 2100002 | Operation failed. Cannot connect to service.|
| 2100003 | System internal error.                  |

**Example**

```js
policy.isUidNetAllowed(11111, 'wlan0', (error, data) => {
  console.log(JSON.stringify(error))
  console.log(JSON.stringify(data))
});
```

## policy.isUidNetAllowed<sup>10+</sup>

isUidNetAllowed(uid: number, iface: string): Promise\<boolean>;

Checks whether the application specified by a given UID is allowed to access the network specified by a given **iface**. This API uses a promise to return the result.

**System API**: This is a system API.

**Required permission**: ohos.permission.MANAGE_NET_STRATEGY

**System capability**: SystemCapability.Communication.NetManager.Core

**Parameters**

| Name  | Type                                   | Mandatory| Description      |
| -------- | --------------------------------------- | ---- | ---------- |
| uid | number | Yes| Unique ID of the application.|
| iface | string | Yes| Name of the target network.|

**Return value**

| Type                             | Description                                 |
| --------------------------------- | ------------------------------------- |
| Promise\<boolean> | Promise used to return the result. |

**Error codes**

| ID| Error Message                                     |
| ------- | -------------------------------------------- |
| 201     | Permission denied.                           |
| 202     | Non-system applications use system APIs.     |
| 401     | Parameter error.                             |
| 2100001 | Invalid parameter value.                     |
| 2100002 | Operation failed. Cannot connect to service.|
| 2100003 | System internal error.                  |

**Example**

```js
policy.isUidNetAllowed(11111, 'wlan0').then(function (error, data) {
  console.log(JSON.stringify(error))
  console.log(JSON.stringify(data))
})
```

## policy.setDeviceIdleTrustlist<sup>10+</sup>

setDeviceIdleTrustlist(uids: Array\<number>, isAllowed: boolean, callback: AsyncCallback\<void>): void

Adds applications specified by given UIDs to the device idle allowlist. This API uses an asynchronous callback to return the result.

**System API**: This is a system API.

**Required permission**: ohos.permission.MANAGE_NET_STRATEGY

**System capability**: SystemCapability.Communication.NetManager.Core

**Parameters**

| Name  | Type                                   | Mandatory| Description      |
| -------- | --------------------------------------- | ---- | ---------- |
| uids | Array\<number> | Yes| Unique ID of the application.|
| isAllowed | boolean | Yes| Whether to add the application to the allowlist.|
| callback | callback: AsyncCallback\<void> | Yes  | Callback used to return the result. If the operation is successful, no value is returned. If the operation fails, an error message is returned.|

**Error codes**

| ID| Error Message                                     |
| ------- | -------------------------------------------- |
| 201     | Permission denied.                           |
| 202     | Non-system applications use system APIs.     |
| 401     | Parameter error.                             |
| 2100001 | Invalid parameter value.                     |
| 2100002 | Operation failed. Cannot connect to service.|
| 2100003 | System internal error.                  |

**Example**

```js
policy.setDeviceIdleTrustlist([11111,22222], true, (error) => {
  console.log(JSON.stringify(error))
});
```

## policy.setDeviceIdleTrustlist<sup>10+</sup>

setDeviceIdleTrustlist(uids: Array\<number>, isAllowed: boolean): Promise\<void>;

Adds applications specified by given UIDs to the device idle allowlist. This API uses a promise to return the result.

**System API**: This is a system API.

**Required permission**: ohos.permission.MANAGE_NET_STRATEGY

**System capability**: SystemCapability.Communication.NetManager.Core

**Parameters**

| Name  | Type                                   | Mandatory| Description      |
| -------- | --------------------------------------- | ---- | ---------- |
| uids | Array\<number> | Yes| Unique ID of the application.|
| isAllowed | boolean | Yes| Whether to add the application to the allowlist.|

**Return value**

| Type                             | Description                                 |
| --------------------------------- | ------------------------------------- |
| Promise\<void> | Promise used to return the result. If the operation is successful, no value is returned. If the operation fails, an error message is returned.|

**Error codes**

| ID| Error Message                                     |
| ------- | -------------------------------------------- |
| 201     | Permission denied.                           |
| 202     | Non-system applications use system APIs.     |
| 401     | Parameter error.                             |
| 2100001 | Invalid parameter value.                     |
| 2100002 | Operation failed. Cannot connect to service.|
| 2100003 | System internal error.                  |

**Example**

```js
policy.setDeviceIdleTrustlist([11111,22222], true).then(function (error) {
  console.log(JSON.stringify(error))
})
```

## policy.getDeviceIdleTrustlist<sup>10+</sup>

getDeviceIdleTrustlist(callback: AsyncCallback\<Array\<number>>): void

Obtains the UIDs of applications that are on the device idle allowlist. This API uses an asynchronous callback to return the result.

**System API**: This is a system API.

**Required permission**: ohos.permission.MANAGE_NET_STRATEGY

**System capability**: SystemCapability.Communication.NetManager.Core

**Parameters**

| Name  | Type                                   | Mandatory| Description      |
| -------- | --------------------------------------- | ---- | ---------- |
| callback | AsyncCallback\<Array\<number>> | Yes  | Callback used to return the result.|

**Error codes**

| ID| Error Message                                     |
| ------- | -------------------------------------------- |
| 201     | Permission denied.                           |
| 202     | Non-system applications use system APIs.     |
| 401     | Parameter error.                             |
| 2100001 | Invalid parameter value.                     |
| 2100002 | Operation failed. Cannot connect to service.|
| 2100003 | System internal error.                  |

**Example**

```js
policy.getDeviceIdleTrustlist((error, data) => {
  console.log(JSON.stringify(error))
  console.log(JSON.stringify(data))
});
```

## policy.getDeviceIdleTrustlist<sup>10+</sup>

getDeviceIdleTrustlist(): Promise\<Array\<number>>;

Obtains the UIDs of applications that are on the device idle allowlist. This API uses a promise to return the result.

**System API**: This is a system API.

**Required permission**: ohos.permission.MANAGE_NET_STRATEGY

**System capability**: SystemCapability.Communication.NetManager.Core

**Return value**

| Type                             | Description                                 |
| --------------------------------- | ------------------------------------- |
| Promise\<Array\<number>> | Promise used to return the result.|

**Error codes**

| ID| Error Message                                     |
| ------- | -------------------------------------------- |
| 201     | Permission denied.                           |
| 202     | Non-system applications use system APIs.     |
| 401     | Parameter error.                             |
| 2100002 | Operation failed. Cannot connect to service.|
| 2100003 | System internal error.                  |
**Example**

```js
policy.getDeviceIdleTrustlist().then(function (error, data) {
  console.log(JSON.stringify(error))
  console.log(JSON.stringify(data))
})
```

## policy.getBackgroundPolicyByUid<sup>10+</sup>

getBackgroundPolicyByUid(uid: number, callback: AsyncCallback\<NetBackgroundPolicy>): void

Obtains the background network policy for the application specified by a given UID. This API uses an asynchronous callback to return the result.

**System API**: This is a system API.

**Required permission**: ohos.permission.MANAGE_NET_STRATEGY

**System capability**: SystemCapability.Communication.NetManager.Core

**Parameters**

| Name  | Type                                   | Mandatory| Description      |
| -------- | --------------------------------------- | ---- | ---------- |
| uid | number | Yes| Unique ID of the application.|
| callback | AsyncCallback\<[NetBackgroundPolicy](#netbackgroundpolicy10)> | Yes  | Callback used to return the result.|

**Error codes**

| ID| Error Message                                     |
| ------- | -------------------------------------------- |
| 201     | Permission denied.                           |
| 202     | Non-system applications use system APIs.     |
| 401     | Parameter error.                             |
| 2100001 | Invalid parameter value.                     |
| 2100002 | Operation failed. Cannot connect to service.|
| 2100003 | System internal error.                  |

**Example**

```js
policy.getBackgroundPolicyByUid(11111, (error, data) => {
  console.log(JSON.stringify(error))
  console.log(JSON.stringify(data))
});
```

## policy.getBackgroundPolicyByUid<sup>10+</sup>

getBackgroundPolicyByUid(uid: number): Promise\<NetBackgroundPolicy>;

Obtains the background network policy for the application specified by a given UID. This API uses a promise to return the result.

**System API**: This is a system API.

**Required permission**: ohos.permission.MANAGE_NET_STRATEGY

**System capability**: SystemCapability.Communication.NetManager.Core

**Parameters**

| Name  | Type                                   | Mandatory| Description      |
| -------- | --------------------------------------- | ---- | ---------- |
| uid | number | Yes| Unique ID of the application.|

**Return value**

| Type                             | Description                                 |
| --------------------------------- | ------------------------------------- |
| Promise\<[NetBackgroundPolicy](#netbackgroundpolicy10)> | Promise used to return the result.|

**Error codes**

| ID| Error Message                                     |
| ------- | -------------------------------------------- |
| 201     | Permission denied.                           |
| 202     | Non-system applications use system APIs.     |
| 401     | Parameter error.                             |
| 2100001 | Invalid parameter value.                     |
| 2100002 | Operation failed. Cannot connect to service.|
| 2100003 | System internal error.                  |

**Example**

```js
policy.getBackgroundPolicyByUid(11111).then(function (error, data) {
  console.log(JSON.stringify(error))
  console.log(JSON.stringify(data))
})
```

## policy.resetPolicies<sup>10+</sup>

resetPolicies(simId: string, callback: AsyncCallback\<void>): void

Restores all the policies (cellular network, background network, firewall, and application-specific network policies) for the specified SIM card. This API uses an asynchronous callback to return the result.

**System API**: This is a system API.

**Required permission**: ohos.permission.MANAGE_NET_STRATEGY

**System capability**: SystemCapability.Communication.NetManager.Core

**Parameters**

| Name  | Type                                   | Mandatory| Description      |
| -------- | --------------------------------------- | ---- | ---------- |
| simId | string | Yes| SIM card ID.|
| callback | AsyncCallback\<void> | Yes  | Callback used to return the result. If the operation is successful, no value is returned. If the operation fails, an error message is returned.|

**Error codes**

| ID| Error Message                                     |
| ------- | -------------------------------------------- |
| 201     | Permission denied.                           |
| 202     | Non-system applications use system APIs.     |
| 401     | Parameter error.                             |
| 2100001 | Invalid parameter value.                     |
| 2100002 | Operation failed. Cannot connect to service.|
| 2100003 | System internal error.                  |

**Example**

```js
policy.resetPolicies('1', (error) => {
  console.log(JSON.stringify(error))
});
```

## policy.resetPolicies<sup>10+</sup>

resetPolicies(simId: string): Promise\<void>;

Restores all the policies (cellular network, background network, firewall, and application-specific network policies) for the specified SIM card. This API uses a promise to return the result.

**System API**: This is a system API.

**Required permission**: ohos.permission.MANAGE_NET_STRATEGY

**System capability**: SystemCapability.Communication.NetManager.Core

**Parameters**

| Name  | Type                                   | Mandatory| Description      |
| -------- | --------------------------------------- | ---- | ---------- |
| simId | string | Yes| SIM card ID.|

**Return value**

| Type                             | Description                                 |
| --------------------------------- | ------------------------------------- |
| Promise\<void> | Promise used to return the result. If the operation is successful, no value is returned. If the operation fails, an error message is returned.|

**Error codes**

| ID| Error Message                                     |
| ------- | -------------------------------------------- |
| 201     | Permission denied.                           |
| 202     | Non-system applications use system APIs.     |
| 401     | Parameter error.                             |
| 2100001 | Invalid parameter value.                     |
| 2100002 | Operation failed. Cannot connect to service.|
| 2100003 | System internal error.                  |

**Example**

```js
policy.resetPolicies('1').then(function (error) {
  console.log(JSON.stringify(error))
})
```

## policy.updateRemindPolicy<sup>10+</sup>

updateRemindPolicy(netType: NetBearType, simId: string, remindType: RemindType, callback: AsyncCallback\<void>): void

Updates a reminder policy. This API uses an asynchronous callback to return the result.

**System API**: This is a system API.

**Required permission**: ohos.permission.MANAGE_NET_STRATEGY

**System capability**: SystemCapability.Communication.NetManager.Core

**Parameters**

| Name  | Type                                   | Mandatory| Description      |
| -------- | --------------------------------------- | ---- | ---------- |
| netType | [NetBearType](js-apis-net-connection.md#netbeartype) | Yes| Network type.|
| simId | string | Yes| SIM card ID.|
| remindType | [RemindType](#remindtype10) | Yes| Reminder type.|
| callback | AsyncCallback\<void> | Yes  | Callback used to return the result. If the operation is successful, no value is returned. If the operation fails, an error message is returned.|

**Error codes**

| ID| Error Message                                     |
| ------- | -------------------------------------------- |
| 201     | Permission denied.                           |
| 202     | Non-system applications use system APIs.     |
| 401     | Parameter error.                             |
| 2100001 | Invalid parameter value.                     |
| 2100002 | Operation failed. Cannot connect to service.|
| 2100003 | System internal error.                  |

**Example**

```js
import connection from '@ohos.net.connection';
policy.updateRemindPolicy(connection.NetBearType.BEARER_CELLULAR, '1', policy.RemindType.REMIND_TYPE_WARNING, (error) => {
  console.log(JSON.stringify(error))
});
```

## policy.updateRemindPolicy<sup>10+</sup>

updateRemindPolicy(netType: NetBearType, simId: string, remindType: RemindType): Promise\<void>;

Updates a reminder policy. This API uses a promise to return the result.

**System API**: This is a system API.

**Required permission**: ohos.permission.MANAGE_NET_STRATEGY

**System capability**: SystemCapability.Communication.NetManager.Core

**Parameters**

| Name  | Type                                   | Mandatory| Description      |
| -------- | --------------------------------------- | ---- | ---------- |
| netType | [NetBearType](js-apis-net-connection.md#netbeartype) | Yes| Network type.|
| simId | string | Yes| SIM card ID.|
| remindType | [RemindType](#remindtype10) | Yes| Reminder type.|

**Return value**

| Type                             | Description                                 |
| --------------------------------- | ------------------------------------- |
| Promise\<void> | Promise used to return the result. If the operation is successful, no value is returned. If the operation fails, an error message is returned.|

**Error codes**

| ID| Error Message                                     |
| ------- | -------------------------------------------- |
| 201     | Permission denied.                           |
| 202     | Non-system applications use system APIs.     |
| 401     | Parameter error.                             |
| 2100001 | Invalid parameter value.                     |
| 2100002 | Operation failed. Cannot connect to service.|
| 2100003 | System internal error.                  |

**Example**

```js
import connection from '@ohos.net.connection';
policy.updateRemindPolicy(connection.NetBearType.BEARER_CELLULAR, '1', policy.RemindType.REMIND_TYPE_WARNING).then(function (error) {
  console.log(JSON.stringify(error))
})
```

## policy.setPowerSaveTrustlist<sup>10+</sup>

setPowerSaveTrustlist(uids: Array\<number>, isAllowed: boolean, callback: AsyncCallback\<void>): void

Sets whether to add the application specified by a given UID to the power-saving allowlist. This API uses an asynchronous callback to return the result.

**System API**: This is a system API.

**Required permission**: ohos.permission.MANAGE_NET_STRATEGY

**System capability**: SystemCapability.Communication.NetManager.Core

**Parameters**

| Name  | Type                                   | Mandatory| Description      |
| -------- | --------------------------------------- | ---- | ---------- |
| uids | Array\<number> | Yes| Unique ID of the application.|
| isAllowed | boolean | Yes| Whether to add the application to the allowlist.|
| callback | callback: AsyncCallback\<void> | Yes  | Callback used to return the result. If the operation is successful, no value is returned. If the operation fails, an error message is returned.|

**Error codes**

| ID| Error Message                                     |
| ------- | -------------------------------------------- |
| 201     | Permission denied.                           |
| 202     | Non-system applications use system APIs.     |
| 401     | Parameter error.                             |
| 2100001 | Invalid parameter value.                     |
| 2100002 | Operation failed. Cannot connect to service.|
| 2100003 | System internal error.                  |

**Example**

```js
policy.setPowerSaveTrustlist([11111,22222], true, (error) => {
  console.log(JSON.stringify(error))
});
```

## policy.setPowerSaveTrustlist<sup>10+</sup>

setPowerSaveTrustlist(uids: Array\<number>, isAllowed: boolean): Promise\<void>;

Sets whether to add the application specified by a given UID to the power-saving allowlist. This API uses a promise to return the result.

**System API**: This is a system API.

**Required permission**: ohos.permission.MANAGE_NET_STRATEGY

**System capability**: SystemCapability.Communication.NetManager.Core

**Parameters**

| Name  | Type                                   | Mandatory| Description      |
| -------- | --------------------------------------- | ---- | ---------- |
| uids | Array\<number> | Yes| Unique ID of the application.|
| isAllowed | boolean | Yes| Whether to add the application to the allowlist.|

**Return value**

| Type                             | Description                                 |
| --------------------------------- | ------------------------------------- |
| Promise\<void> | Promise used to return the result. If the operation is successful, no value is returned. If the operation fails, an error message is returned.|

**Error codes**

| ID| Error Message                                     |
| ------- | -------------------------------------------- |
| 201     | Permission denied.                           |
| 202     | Non-system applications use system APIs.     |
| 401     | Parameter error.                             |
| 2100001 | Invalid parameter value.                     |
| 2100002 | Operation failed. Cannot connect to service.|
| 2100003 | System internal error.                  |

**Example**

```js
policy.setPowerSaveTrustlist([11111,22222], true).then(function (error) {
  console.log(JSON.stringify(error))
})
```

## policy.getPowerSaveTrustlist<sup>10+</sup>

getPowerSaveTrustlist(callback: AsyncCallback\<Array\<number>>): void

Obtains the UID array of applications that are on the power-saving allowlist. This API uses an asynchronous callback to return the result.

**System API**: This is a system API.

**Required permission**: ohos.permission.MANAGE_NET_STRATEGY

**System capability**: SystemCapability.Communication.NetManager.Core

**Parameters**

| Name  | Type                                   | Mandatory| Description      |
| -------- | --------------------------------------- | ---- | ---------- |
| callback | AsyncCallback\<Array\<number>> | Yes  | Callback used to return the result.|

**Error codes**

| ID| Error Message                                     |
| ------- | -------------------------------------------- |
| 201     | Permission denied.                           |
| 202     | Non-system applications use system APIs.     |
| 401     | Parameter error.                             |
| 2100001 | Invalid parameter value.                     |
| 2100002 | Operation failed. Cannot connect to service.|
| 2100003 | System internal error.                  |

**Example**

```js
policy.getPowerSaveTrustlist((error, data) => {
  console.log(JSON.stringify(error))
  console.log(JSON.stringify(data))
});
```

## policy.getPowerSaveTrustlist<sup>10+</sup>

getPowerSaveTrustlist(): Promise\<Array\<number>>;

Obtains the UID array of applications that are on the device idle allowlist. This API uses a promise to return the result.

**System API**: This is a system API.

**Required permission**: ohos.permission.MANAGE_NET_STRATEGY

**System capability**: SystemCapability.Communication.NetManager.Core

**Return value**

| Type                             | Description                                 |
| --------------------------------- | ------------------------------------- |
| Promise\<Array\<number>> | Promise used to return the result.|

**Error codes**

| ID| Error Message                                     |
| ------- | -------------------------------------------- |
| 201     | Permission denied.                           |
| 202     | Non-system applications use system APIs.     |
| 401     | Parameter error.                             |
| 2100002 | Operation failed. Cannot connect to service.|
| 2100003 | System internal error.                  |

**Example**

```js
policy.getPowerSaveTrustlist().then(function (error, data) {
  console.log(JSON.stringify(error))
  console.log(JSON.stringify(data))
})
```

## policy.on

Represents the handle to a network policy.

### on('netUidPolicyChange')<sup>10+</sup>

on(type: "netUidPolicyChange", callback: Callback\<{ uid: number, policy: NetUidPolicy }>): void

Subscribes to policy changes. This API uses an asynchronous callback to return the result.

**System API**: This is a system API.

**Required permission**: ohos.permission.MANAGE_NET_STRATEGY

**System capability**: SystemCapability.Communication.NetManager.Core

**Parameters**

| Name  | Type                              | Mandatory| Description                                                        |
| -------- | ---------------------------------- | ---- | ------------------------------------------------------------ |
| type | string | Yes| Event type. The value **netUidPolicyChange** indicates a policy change event.|
| callback | Callback\<{ uid: number, policy: [NetUidPolicy](#netuidpolicy10) }> | Yes  | Callback used to return the result. It is called when the registered network policy changes.|

**Error codes**

| ID| Error Message                                     |
| ------- | -------------------------------------------- |
| 201     | Permission denied.                           |
| 202     | Non-system applications use system APIs.     |
| 401     | Parameter error.                             |
| 2100001 | Invalid parameter value.                     |
| 2100002 | Operation failed. Cannot connect to service.|
| 2100003 | System internal error.        

**Example**

```js
policy.on('netUidPolicyChange', (data) => {
  console.log('on netUidPolicyChange: ' + JSON.stringify(data));
})
```

### off('netUidPolicyChange')<sup>10+</sup>

off(type: "netUidPolicyChange", callback?: Callback<{ uid: number, policy: NetUidPolicy }>): void

Unsubscribes from policy changes. This API uses an asynchronous callback to return the result.

**System API**: This is a system API.

**Required permission**: ohos.permission.MANAGE_NET_STRATEGY

**System capability**: SystemCapability.Communication.NetManager.Core

**Parameters**

| Name  | Type                              | Mandatory| Description                                                        |
| -------- | ---------------------------------- | ---- | ------------------------------------------------------------ |
| type | string | Yes| Event type. The value **netUidPolicyChange** indicates a policy change event.|
| callback | Callback\<{ uid: number, policy: [NetUidPolicy](#netuidpolicy10) }> | No  | Callback used to return the result. It is called when the registered network policy changes.|

**Error codes**

| ID| Error Message                                     |
| ------- | -------------------------------------------- |
| 201     | Permission denied.                           |
| 202     | Non-system applications use system APIs.     |
| 401     | Parameter error.                             |
| 2100001 | Invalid parameter value.                     |
| 2100002 | Operation failed. Cannot connect to service.|
| 2100003 | System internal error.        

**Example**

```js
let callback = data => {
    console.log("on netUidPolicyChange, data:" + JSON.stringify(data));
}
policy.on('netUidPolicyChange', callback);
policy.off('netUidPolicyChange', callback);
```

### on('netUidRuleChange')<sup>10+</sup>

on(type: "netUidRuleChange", callback: Callback\<{ uid: number, rule: NetUidRule }>): void

Subscribes to rule changes. This API uses an asynchronous callback to return the result.

**System API**: This is a system API.

**Required permission**: ohos.permission.MANAGE_NET_STRATEGY

**System capability**: SystemCapability.Communication.NetManager.Core

**Parameters**

| Name  | Type                              | Mandatory| Description                                                        |
| -------- | ---------------------------------- | ---- | ------------------------------------------------------------ |
| type | string | Yes| Event type. The value **netUidRuleChange** indicates a rule change event.|
| callback | Callback\<{ uid: number, rule: [NetUidRule](#netuidrule10) }> | Yes  | Callback used to return the result. It is called when the registered rule changes.|

**Error codes**

| ID| Error Message                                     |
| ------- | -------------------------------------------- |
| 201     | Permission denied.                           |
| 202     | Non-system applications use system APIs.     |
| 401     | Parameter error.                             |
| 2100001 | Invalid parameter value.                     |
| 2100002 | Operation failed. Cannot connect to service.|
| 2100003 | System internal error.        

**Example**

```js
policy.on('netUidRuleChange', (data) => {
  console.log('on netUidRuleChange: ' + JSON.stringify(data));
})
```

### off('netUidRuleChange')<sup>10+</sup>

off(type: "netUidRuleChange", callback?: Callback<{ uid: number, rule: NetUidRule }>): void

Unsubscribes from rule changes. This API uses an asynchronous callback to return the result.

**System API**: This is a system API.

**Required permission**: ohos.permission.MANAGE_NET_STRATEGY

**System capability**: SystemCapability.Communication.NetManager.Core

**Parameters**

| Name  | Type                              | Mandatory| Description                                                        |
| -------- | ---------------------------------- | ---- | ------------------------------------------------------------ |
| type | string | Yes| Event type. The value **netUidRuleChange** indicates a rule change event.|
| callback | Callback\<{ uid: number, rule: [NetUidRule](#netuidrule10) }> | No  | Callback used to return the result. It is called when the registered rule changes.|

**Error codes**

| ID| Error Message                                     |
| ------- | -------------------------------------------- |
| 201     | Permission denied.                           |
| 202     | Non-system applications use system APIs.     |
| 401     | Parameter error.                             |
| 2100001 | Invalid parameter value.                     |
| 2100002 | Operation failed. Cannot connect to service.|
| 2100003 | System internal error.        

**Example**

```js
let callback = data => {
    console.log("on netUidRuleChange, data:" + JSON.stringify(data));
}
policy.on('netUidRuleChange', callback);
policy.off('netUidRuleChange', callback);
```

### on('netMeteredIfacesChange')<sup>10+</sup>

on(type: "netMeteredIfacesChange", callback: Callback\<Array\<string>>): void

Subscribes to metered **iface** changes. This API uses an asynchronous callback to return the result.

**System API**: This is a system API.

**Required permission**: ohos.permission.MANAGE_NET_STRATEGY

**System capability**: SystemCapability.Communication.NetManager.Core

**Parameters**

| Name  | Type                              | Mandatory| Description                                                        |
| -------- | ---------------------------------- | ---- | ------------------------------------------------------------ |
| type | string | Yes| Event type. The value **netMeteredIfacesChange** indicates a metered **iface** change event.|
| callback | Callback\<Array\<string>> | Yes  | Callback used to return the result. It is called when the registered metered **iface** changes.|

**Error codes**

| ID| Error Message                                     |
| ------- | -------------------------------------------- |
| 201     | Permission denied.                           |
| 202     | Non-system applications use system APIs.     |
| 401     | Parameter error.                             |
| 2100001 | Invalid parameter value.                     |
| 2100002 | Operation failed. Cannot connect to service.|
| 2100003 | System internal error.        

**Example**

```js
policy.on('netMeteredIfacesChange', (data) => {
  console.log('on netMeteredIfacesChange: ' + JSON.stringify(data));
})
```

### off('netMeteredIfacesChange')<sup>10+</sup>

off(type: "netMeteredIfacesChange", callback?: Callback\<Array\<string>>): void

Unsubscribes from metered **iface** changes. This API uses an asynchronous callback to return the result.

**System API**: This is a system API.

**Required permission**: ohos.permission.MANAGE_NET_STRATEGY

**System capability**: SystemCapability.Communication.NetManager.Core

**Parameters**

| Name  | Type                              | Mandatory| Description                                                        |
| -------- | ---------------------------------- | ---- | ------------------------------------------------------------ |
| type | string | Yes| Event type. The value **netMeteredIfacesChange** indicates a metered **iface** change event.|
| callback | Callback\<Array\<string>> | No  | Callback used to return the result. It is called when the registered metered **iface** changes.|

**Error codes**

| ID| Error Message                                     |
| ------- | -------------------------------------------- |
| 201     | Permission denied.                           |
| 202     | Non-system applications use system APIs.     |
| 401     | Parameter error.                             |
| 2100001 | Invalid parameter value.                     |
| 2100002 | Operation failed. Cannot connect to service.|
| 2100003 | System internal error.        

**Example**

```js
let callback = data => {
    console.log("on netMeteredIfacesChange, data:" + JSON.stringify(data));
}
policy.on('netMeteredIfacesChange', callback);
policy.off('netMeteredIfacesChange', callback);
```

### on('netQuotaPolicyChange')<sup>10+</sup>

on(type: "netQuotaPolicyChange", callback: Callback\<Array\<NetQuotaPolicy>>): void

Subscribes to network quota policy changes. This API uses an asynchronous callback to return the result.

**System API**: This is a system API.

**Required permission**: ohos.permission.MANAGE_NET_STRATEGY

**System capability**: SystemCapability.Communication.NetManager.Core

**Parameters**

| Name  | Type                              | Mandatory| Description                                                        |
| -------- | ---------------------------------- | ---- | ------------------------------------------------------------ |
| type | string | Yes| Event type. The value **netQuotaPolicyChange** indicates a network quota policy change event.|
| callback | Callback\<Array\<[NetQuotaPolicy](#netquotapolicy10)>> | Yes  | Callback used to return the result. It is called when the registered network quota policy changes.|

**Error codes**

| ID| Error Message                                     |
| ------- | -------------------------------------------- |
| 201     | Permission denied.                           |
| 202     | Non-system applications use system APIs.     |
| 401     | Parameter error.                             |
| 2100001 | Invalid parameter value.                     |
| 2100002 | Operation failed. Cannot connect to service.|
| 2100003 | System internal error.        

**Example**

```js
policy.on('netQuotaPolicyChange', (data) => {
  console.log('on netQuotaPolicyChange: ' + JSON.stringify(data));
})
```

### off('netQuotaPolicyChange')<sup>10+</sup>

off(type: "netQuotaPolicyChange", callback?: Callback\<Array\<NetQuotaPolicy>>): void

Unsubscribes from network quota policy changes. This API uses an asynchronous callback to return the result.

**System API**: This is a system API.

**Required permission**: ohos.permission.MANAGE_NET_STRATEGY

**System capability**: SystemCapability.Communication.NetManager.Core

**Parameters**

| Name  | Type                              | Mandatory| Description                                                        |
| -------- | ---------------------------------- | ---- | ------------------------------------------------------------ |
| type | string | Yes| Event type. The value **netQuotaPolicyChange** indicates a network quota policy change event.|
| callback | Callback\<Array\<[NetQuotaPolicy](#netquotapolicy10)>> | No  | Callback used to return the result. It is called when the registered network quota policy changes.|

**Error codes**

| ID| Error Message                                     |
| ------- | -------------------------------------------- |
| 201     | Permission denied.                           |
| 202     | Non-system applications use system APIs.     |
| 401     | Parameter error.                             |
| 2100001 | Invalid parameter value.                     |
| 2100002 | Operation failed. Cannot connect to service.|
| 2100003 | System internal error.        

**Example**

```js
let callback = data => {
    console.log("on netQuotaPolicyChange, data:" + JSON.stringify(data));
}
policy.on('netQuotaPolicyChange', callback);
policy.off('netQuotaPolicyChange', callback);
```

### on('netBackgroundPolicyChange')<sup>10+</sup>

on(type: "netBackgroundPolicyChange", callback: Callback\<boolean>): void

Subscribes to background network policy changes. This API uses an asynchronous callback to return the result.

**System API**: This is a system API.

**Required permission**: ohos.permission.MANAGE_NET_STRATEGY

**System capability**: SystemCapability.Communication.NetManager.Core

**Parameters**

| Name  | Type                              | Mandatory| Description                                                        |
| -------- | ---------------------------------- | ---- | ------------------------------------------------------------ |
| type | string | Yes| Event type. The value **netBackgroundPolicyChange** indicates a background network policy change event.|
| callback | Callback\<boolean> | Yes  | Callback used to return the result. It is called when the registered background network policy changes.|

**Error codes**

| ID| Error Message                                     |
| ------- | -------------------------------------------- |
| 201     | Permission denied.                           |
| 202     | Non-system applications use system APIs.     |
| 401     | Parameter error.                             |
| 2100001 | Invalid parameter value.                     |
| 2100002 | Operation failed. Cannot connect to service.|
| 2100003 | System internal error.        

**Example**

```js
policy.on('netBackgroundPolicyChange', (data) => {
  console.log('on netBackgroundPolicyChange: ' + JSON.stringify(data));
})
```

### off('netBackgroundPolicyChange')<sup>10+</sup>

off(type: "netBackgroundPolicyChange", callback?: Callback\<boolean>): void

Unsubscribes from background network policy changes. This API uses an asynchronous callback to return the result.

**System API**: This is a system API.

**Required permission**: ohos.permission.MANAGE_NET_STRATEGY

**System capability**: SystemCapability.Communication.NetManager.Core

**Parameters**

| Name  | Type                              | Mandatory| Description                                                        |
| -------- | ---------------------------------- | ---- | ------------------------------------------------------------ |
| type | string | Yes| Event type. The value **netBackgroundPolicyChange** indicates a background network policy change event.|
| callback | Callback\<boolean> | No  | Callback used to return the result. It is called when the registered background network policy changes.|

**Error codes**

| ID| Error Message                                     |
| ------- | -------------------------------------------- |
| 201     | Permission denied.                           |
| 202     | Non-system applications use system APIs.     |
| 401     | Parameter error.                             |
| 2100001 | Invalid parameter value.                     |
| 2100002 | Operation failed. Cannot connect to service.|
| 2100003 | System internal error.        

**Example**

```js
let callback = data => {
    console.log("on netBackgroundPolicyChange, data:" + JSON.stringify(data));
}
policy.on('netBackgroundPolicyChange', callback);
policy.off('netBackgroundPolicyChange', callback);
```

## NetBackgroundPolicy<sup>10+</sup>

Enumerates the background network policies.

**System API**: This is a system API.

**System capability**: SystemCapability.Communication.NetManager.Core

| Name                 | Value  | Description                  |
| ------------------------ | ---- | ---------------------- |
| NET_BACKGROUND_POLICY_NONE       | 0 | Default policy.|
| NET_BACKGROUND_POLICY_ENABLE     | 1 | Background applications are allowed to access a metered network.|
| NET_BACKGROUND_POLICY_DISABLE    | 2 | Applications running in the background are not allowed to access a metered network.|
| NET_BACKGROUND_POLICY_TRUSTLIST | 3 | Only applications on the allowlist are allowed to access metered networks when they are running in the background.|

## NetQuotaPolicy<sup>10+</sup>

Defines the quota policy for the specified network.

**System API**: This is a system API.

**System capability**: SystemCapability.Communication.NetManager.Core

| Name                 | Type                               |Mandatory| Description                                                        |
| ----------------------- | ----------------------------------- |------| -------------------------------------------------------  |
| networkMatchRule             | [NetworkMatchRule](#networkmatchrule10)               |Yes| Network for which the quota policy is set.
| quotaPolicy             | [QuotaPolicy](#quotapolicy10)                      |Yes| Network quota policy.

## NetworkMatchRule<sup>10+</sup>

Defines the network for which the quota policy is set.

**System API**: This is a system API.

**System capability**: SystemCapability.Communication.NetManager.Core

| Name                 | Type                               |Mandatory| Description                                                        |
| ----------------------- | ----------------------------------- |-----| ------------------------------------------------------------ |
| netType           | [NetBearType](js-apis-net-connection.md#netbeartype) |Yes| Network type.|
| simId             | string                      |Yes| Identifier of the SIM card on the metered cellular network. It is not used for Wi-Fi networks.|
| identity             | string                      |Yes| ID of the SIM card on the metered cellular network. It is used for Wi-Fi networks. It is used together with **iccid**.|

## QuotaPolicy<sup>10+</sup>

Defines the network quota policy.

**System API**: This is a system API.

**System capability**: SystemCapability.Communication.NetManager.Core

| Name                 | Type                               |Mandatory| Description                                                        |
| ----------------------- | ----------------------------------- |----| ------------------------------------------------------------ |
| periodDuration    | string                      |Yes| Metering period for the quota limit. **D1**, **M1**, and **Y1** indicate one day, one month, and one year, respectively. If the specified metering period is exceeded, the quota is not limited.|
| warningBytes      | number                      |Yes| Data volume threshold for generating an alarm.|
| limitBytes        | number                      |Yes| Data volume quota.|
| metered           | string                      |Yes| Whether the network is a metered network.|
| limitAction       | [LimitAction](#limitaction10) |Yes| Action to take when the data volume quota is reached.|
| lastWarningRemind | string                      |No| Last time when an alarm was generated.|
| lastLimitRemind   | string                      |No| Last time when the quota was exhausted.|

## LimitAction<sup>10+</sup>

Enumerates the actions that can be taken when the data volume quota is reached.

**System API**: This is a system API.

**System capability**: SystemCapability.Communication.NetManager.Core

| Name                 | Value| Description  |
| ---------------------- | ----- | ------------ |
| LIMIT_ACTION_NONE     | -1 | No action is taken. This is the default value.|
| LIMIT_ACTION_ACCESS_DISABLED  | 0  | Internet access is disabled.|
| LIMIT_ACTION_ALERT_ONLY| 1  | An alarm is generated when the quota limit is reached.|

## NetUidRule<sup>10+</sup>

Enumerates the metered network rules.

**System API**: This is a system API.

**System capability**: SystemCapability.Communication.NetManager.Core

| Name                | Value| Description  |
| ---------------------- | ----- | ------------ |
| NET_RULE_NONE                     | 0 | Default rule.|
| NET_RULE_ALLOW_METERED_FOREGROUND | 1 << 0 | Applications running in the foreground are allowed to access a metered network.|
| NET_RULE_ALLOW_METERED            | 1 << 1 | Applications are allowed to access a metered network.|
| NET_RULE_REJECT_METERED           | 1 << 2 | Applications are not allowed to access a metered network.|
| NET_RULE_ALLOW_ALL                | 1 << 5 | Applications are allowed to access all networks (metered or non-metered).|
| NET_RULE_REJECT_ALL               | 1 << 6 | Applications are not allowed to access any networks (metered or non-metered).|

## RemindType<sup>10+</sup>

Enumerates the reminder types.

**System API**: This is a system API.

**System capability**: SystemCapability.Communication.NetManager.Core

| Name| Value| Description|
| ---------------------- | - | ------- |
| REMIND_TYPE_WARNING | 1 | Warning.|
| REMIND_TYPE_LIMIT   | 2 | Limit.|

## NetUidPolicy<sup>10+</sup>

Enumerates network access policies for the application.

**System API**: This is a system API.

**System capability**: SystemCapability.Communication.NetManager.Core

| Name                 | Value| Description  |
| ---------------------- | ----- | ------------ |
| NET_POLICY_NONE                       | 0 | Default network policy.|
| NET_POLICY_ALLOW_METERED_BACKGROUND   | 1 << 0 | Background applications are allowed to access a metered network.|
| NET_POLICY_REJECT_METERED_BACKGROUND  | 1 << 1 | Applications running in the background are not allowed to access a metered network.|