# Cellular Data
>**NOTE**
>
>The initial APIs of this module are supported since API version 7. Newly added APIs will be marked with a superscript to indicate their earliest API version.
## Modules to Import
```
import data from '@ohos.telephony.data';
```
## data.getDefaultCellularDataSlotId
getDefaultCellularDataSlotId(callback: AsyncCallback\): void
Obtains the default SIM card used for mobile data. This function uses an asynchronous callback to return the result.
**Required permission**: ohos.permission.GET_NETWORK_INFO
**System capability**: SystemCapability.Telephony.CellularData
**Parameters**
| Name| Type| Mandatory| Description|
| -------- | ----------------------- | ---- | ------------------------------------------ |
| callback | AsyncCallback\ | Yes| Callback used to return the result.
**0**: slot 1
**1**: slot 2|
**Example**
```
data.getDefaultCellularDataSlotId((err, data) => {
console.log(`callback: err->${JSON.stringify(err)}, data->${JSON.stringify(data)}`);
});
```
## data.getDefaultCellularDataSlotId
getDefaultCellularDataSlotId(): Promise\
Obtains the default SIM card used for mobile data. This function uses a promise to return the result.
**Required permission**: ohos.permission.GET_NETWORK_INFO
**System capability**: SystemCapability.Telephony.CellularData
**Return value**
| Type| Description|
| ----------------- | ------------------------------------------------------------ |
| Promise\ | Promise used to return the result, wherein:
**0**: slot 1
**1**: slot 2|
**Example**
```
let promise = data.getDefaultCellularDataSlotId();
promise.then((data) => {
console.log(`test success, promise: data->${JSON.stringify(data)}`);
}).catch((err) => {
console.error(`test fail, promise: err->${JSON.stringify(err)}`);
});
```
## data.getCellularDataFlowType
getCellularDataFlowType(callback: AsyncCallback\): void
Obtains the cellular data flow type, which can be uplink or downlink. This function uses an asynchronous callback to return the result.
**System capability**: SystemCapability.Telephony.CellularData
**Parameters**
| Name| Type| Mandatory| Description|
| -------- | ---------------------------------------------- | ---- | ---------- |
| callback | AsyncCallback\<[DataFlowType](#DataFlowType)\> | Yes| Callback used to return the result.|
**Example**
```
data.getCellularDataFlowType((err, data) => {
console.log(`callback: err->${JSON.stringify(err)}, data->${JSON.stringify(data)}`);
});
```
## data.getCellularDataFlowType
getCellularDataFlowType(): Promise\
Obtains the cellular data flow type, which can be uplink or downlink. This function uses a promise to return the result.
**System capability**: SystemCapability.Telephony.CellularData
**Return value**
| Type| Description|
| ---------------------------------------- | ----------------------------------------------- |
| Promise\<[DataFlowType](#DataFlowType)\> | Promise used to return the result. |
**Example**
```
let promise = data.getCellularDataFlowType();
promise.then((data) => {
console.log(`test success, promise: data->${JSON.stringify(data)}`);
}).catch((err) => {
console.error(`test fail, promise: err->${JSON.stringify(err)}`);
});
```
## data.getCellularDataState
getCellularDataState(callback: AsyncCallback\): void
Obtains the connection status of the packet switched (PS) domain. This function uses an asynchronous callback to return the result.
**System capability**: SystemCapability.Telephony.CellularData
**Parameters**
| Name| Type| Mandatory| Description|
| -------- | ------------------------------------------------------ | ---- | ---------- |
| callback | AsyncCallback\<[DataConnectState](#DataConnectState)\> | Yes| Callback used to return the result.|
**Example**
```
data.getCellularDataState((err, data) => {
console.log(`callback: err->${JSON.stringify(err)}, data->${JSON.stringify(data)}`);
});
```
## data.getCellularDataState
getCellularDataState(): Promise\
Obtains the connection status of the PS domain. This function uses a promise to return the result.
**System capability**: SystemCapability.Telephony.CellularData
**Return value**
| Type| Description|
| ------------------------------------------------ | ------------------------------------- |
| Promise\<[DataConnectState](#DataConnectState)\> | Promise used to return the result.|
**Example**
```
let promise = data.getCellularDataState();
promise.then((data) => {
console.log(`test success, promise: data->${JSON.stringify(data)}`);
}).catch((err) => {
console.error(`test fail, promise: err->${JSON.stringify(err)}`);
});
```
## data.isCellularDataEnabled
isCellularDataEnabled(callback: AsyncCallback\): void
Checks whether the cellular data service is enabled. This function uses an asynchronous callback to return the result.
**Required permission**: ohos.permission.GET_NETWORK_INFO
**System capability**: SystemCapability.Telephony.CellularData
**Parameters**
| Name| Type| Mandatory| Description|
| -------- | ------------------------ | ---- | ------------------------------------------------------------ |
| callback | AsyncCallback\ | Yes| Callback used to return the result.
**true**: The cellular data service is enabled.
**false**: The cellular data service is disabled.|
**Example**
```
data.isCellularDataEnabled((err, data) => {
console.log(`callback: err->${JSON.stringify(err)}, data->${JSON.stringify(data)}`);
});
```
## data.isCellularDataEnabled
isCellularDataEnabled(): Promise\
Checks whether the cellular data service is enabled. This function uses a promise to return the result.
**Required permission**: ohos.permission.GET_NETWORK_INFO
**System capability**: SystemCapability.Telephony.CellularData
**Return value**
| Type| Description|
| ------------------ | ------------------------------------------------------------ |
| Promise\ | Promise used to return the result, wherein:
**true**: The cellular data service is enabled.
**false**: The cellular data service is disabled.|
**Example**
```
let promise = data.isCellularDataEnabled();
promise.then((data) => {
console.log(`test success, promise: data->${JSON.stringify(data)}`);
}).catch((err) => {
console.error(`test fail, promise: err->${JSON.stringify(err)}`);
});
```
## data.isCellularDataRoamingEnabled
isCellularDataRoamingEnabled(slotId: number, callback: AsyncCallback\): void
Checks whether roaming is enabled for the cellular data service. This function uses an asynchronous callback to return the result.
**Required permission**: ohos.permission.GET_NETWORK_INFO
**System capability**: SystemCapability.Telephony.CellularData
**Parameters**
| Name| Type| Mandatory| Description|
| -------- | ------------------------ | ---- | ------------------------------------------------------------ |
| slotId | number | Yes| Card slot ID. The options are as follows:
**0**: slot 1
**1**: slot 2|
| callback | AsyncCallback\ | Yes| Callback used to return the result.
**true**: Roaming is enabled for the cellular data service.
**false**: Roaming is disabled for the cellular data service.|
**Example**
```
data.isCellularDataRoamingEnabled(0,(err, data) => {
console.log(`callback: err->${JSON.stringify(err)}, data->${JSON.stringify(data)}`);
});
```
## data.isCellularDataRoamingEnabled
isCellularDataRoamingEnabled(slotId: number): Promise\
Checks whether roaming is enabled for the cellular data service. This method uses a promise to return the result.
**Required permission**: ohos.permission.GET_NETWORK_INFO
**System capability**: SystemCapability.Telephony.CellularData
**Parameters**
| Name| Type| Mandatory| Description|
| ------ | ------ | ---- | ---------------------------------------- |
| slotId | number | Yes| Card slot ID. The options are as follows:
**0**: slot 1
**1**: slot 2|
**Return value**
| Type| Description|
| ------------------ | ------------------------------------------------------------ |
| Promise\ | Promise used to return the result, wherein:
**true**: Roaming is enabled for the cellular data service.
**false**: Roaming is disabled for the cellular data service.|
**Example**
```
let promise = data.isCellularDataRoamingEnabled(0);
promise.then((data) => {
console.log(`test success, promise: data->${JSON.stringify(data)}`);
}).catch((err) => {
console.error(`test fail, promise: err->${JSON.stringify(err)}`);
});
```
## DataFlowType
Defines the cellular data flow type.
| Name| Value| Description|
| ------ | ---------------------- | ------------------------------------------------------------ |
| 0 | DATA_FLOW_TYPE_NONE | No uplink or downlink data is available.
**System capability**: SystemCapability.Telephony.CellularData|
| 1 | DATA_FLOW_TYPE_DOWN | Only the downlink data is available.
**System capability**: SystemCapability.Telephony.CellularData|
| 2 | DATA_FLOW_TYPE_UP | Only the uplink data is available.
**System capability**: SystemCapability.Telephony.CellularData|
| 3 | DATA_FLOW_TYPE_UP_DOWN | Both uplink data and downlink data are available.
**System capability**: SystemCapability.Telephony.CellularData|
| 4 | DATA_FLOW_TYPE_DORMANT | No uplink or downlink data is available because the lower-layer link is in the dormant state.
**System capability**: SystemCapability.Telephony.CellularData|
## DataConnectState
Describes the connection status of a cellular data link.
| Name| Value| Description|
| ------ | ----------------------- | ------------------------------------------------------------ |
| -1 | DATA_STATE_UNKNOWN| The status of the cellular data link is unknown.
**System capability**: SystemCapability.Telephony.CellularData|
| 0 | DATA_STATE_DISCONNECTED | The cellular data link is disconnected.
**System capability**: SystemCapability.Telephony.CellularData|
| 1 | DATA_STATE_CONNECTING | The cellular data link is being connected.
**System capability**: SystemCapability.Telephony.CellularData|
| 2 | DATA_STATE_CONNECTED | The cellular data link is connected.
**System capability**: SystemCapability.Telephony.CellularData|
| 3 | DATA_STATE_SUSPENDED | The cellular data link is suspended.
**System capability**: SystemCapability.Telephony.CellularData|