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!15234 [翻译完成】#I6DYG9 

Merge pull request !15234 from Annie_wang/PR14435
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en/application-dev/database/database-datashare-guidelines.md
浏览文件 @ 7e9154af
......@@ -13,7 +13,7 @@ The **DataShare** module allows an application to manage its own data and share
|query?(uri: string, predicates: DataSharePredicates, columns: Array<string>, callback: AsyncCallback<Object>): void|Queries data from the database.|
|delete?(uri: string, predicates: DataSharePredicates, callback: AsyncCallback<number>): void|Deletes data from the database.|
For details about the data provider APIs, see [DataShareExtensionAbility](../reference/apis/js-apis-application-DataShareExtensionAbility.md).
For details about the data provider APIs, see [DataShareExtensionAbility](../reference/apis/js-apis-application-dataShareExtensionAbility.md).
**Table 2** APIs of the data consumer
......@@ -34,11 +34,49 @@ There are two roles in **DataShare**:
- Data provider: adds, deletes, modifies, and queries data, opens files, and shares data.
- Data consumer: accesses the data provided by the provider using **DataShareHelper**.
Examples are given below.
### Data Provider Application Development (Only for System Applications)
1. Import dependencies.
[DataShareExtensionAbility](../reference/apis/js-apis-application-dataShareExtensionAbility.md) provides the following APIs. You can override these APIs as required.
- **onCreate**
Called by the server to initialize service logic when the **DataShare** client connects to the **DataShareExtensionAbility** server.
- **insert**
Inserts data. This API is called when the client requests to insert data.
- **update**
Updates data. This API is called when the client requests to update data.
- **delete**
Deletes data. This API is called when the client requests to delete data.
- **query**
Queries data. This API is called when the client requests to query data.
- **batchInsert**
Batch inserts data. This API is called when the client requests to batch insert data.
- **normalizeUri**
Converts the URI provided by the client to the URI used by the server.
- **denormalizeUri**
Converts the URI used by the server to the initial URI passed by the client.
Before implementing a **DataShare** service, you need to create a **DataShareExtensionAbility** object in the DevEco Studio project as follows:
1. In the **ets** directory of the **Module** project, right-click and choose **New > Directory** to create a directory named **DataShareAbility**.
2. Right-click the **DataShareAbility** directory, and choose **New > TypeScript File** to create a file named **DataShareAbility.ts**.
3. In the **DataShareAbility.ts** file, import **DataShareExtensionAbility** and other dependencies.
```ts
import Extension from '@ohos.application.DataShareExtensionAbility';
......@@ -47,9 +85,9 @@ Examples are given below.
import dataSharePredicates from '@ohos.data.dataSharePredicates';
```
2. Override **DataShareExtensionAbility** APIs based on actual requirements. For example, if the data provider provides only data query, override only **query()**.
4. Override **DataShareExtensionAbility** APIs based on actual requirements. For example, if the data provider provides only data query, override only **query()**.
3. Implement the data provider services. For example, implement data storage of the data provider by using a database, reading and writing files, or accessing the network.
5. Implement the data provider services. For example, implement data storage of the data provider by using a database, reading and writing files, or accessing the network.
```ts
const DB_NAME = "DB00.db";
......@@ -63,20 +101,22 @@ Examples are given below.
export default class DataShareExtAbility extends Extension {
private rdbStore_;
// Override onCreate().
onCreate(want, callback) {
result = this.context.cacheDir + '/datashare.txt'
result = this.context.cacheDir + '/datashare.txt';
// Create an RDB store.
rdb.getRdbStore(this.context, {
name: DB_NAME,
securityLevel: rdb.SecurityLevel.S1
}, function (err, data) {
rdbStore = data;
rdbStore.executeSql(DDL_TBL_CREATE, [], function (err) {
console.log('DataShareExtAbility onCreate, executeSql done err:' + JSON.stringify(err));
rdb.getRdbStore(this.context, {
name: DB_NAME,
securityLevel: rdb.SecurityLevel.S1
}, function (err, data) {
rdbStore = data;
rdbStore.executeSql(DDL_TBL_CREATE, [], function (err) {
console.log('DataShareExtAbility onCreate, executeSql done err:' + JSON.stringify(err));
});
callback();
if (callback) {
callback();
}
});
}
......@@ -103,19 +143,20 @@ Examples are given below.
};
```
4. Define **DataShareExtensionAbility** in **module.json5**.
| Field| Description |
| ------------ | ------------------------------------------------------------ |
| "name" | Ability name, corresponding to the **ExtensionAbility** class name derived from **Ability**. |
| "type" | Ability type. The value is **dataShare**, indicating the development is based on the **datashare** template.|
| "uri" | URI used for communication. It is the unique identifier for the data consumer to connect to the provider. |
| "visible" | Whether it is visible to other applications. Data sharing is allowed only when the value is **true**.|
6. Define **DataShareExtensionAbility** in **module.json5**.
**module.json5 example**
| Field | Description |
| --------- | ------------------------------------------------------------ |
| "name" | Ability name, corresponding to the **ExtensionAbility** class name derived from **Ability**. |
| "type" | Ability type. The value is **dataShare**, indicating the development is based on the **datashare** template. |
| "uri" | URI used for communication. It is the unique identifier for the data consumer to connect to the provider. |
| "visible" | Whether it is visible to other applications. Data sharing is allowed only when the value is **true**. |
**module.json5 example**
```json
"extensionAbilities": [
"extensionAbilities": [
{
"srcEntrance": "./ets/DataShareExtAbility/DataShareExtAbility.ts",
"name": "DataShareExtAbility",
......@@ -127,31 +168,33 @@ Examples are given below.
}
]
```
### Data Consumer Application Development
1. Import dependencies.
```ts
import Ability from '@ohos.application.Ability';
import UIAbility from '@ohos.app.ability.UIAbility';
import dataShare from '@ohos.data.dataShare';
import dataSharePredicates from '@ohos.data.dataSharePredicates';
```
2. Define the URI string for communicating with the data provider.
```ts
// Different from the URI defined in the module.json5 file, the URI passed in the parameter has an extra slash (/), because there is a DeviceID parameter between the second and the third slash (/).
let dseUri = ("datashare:///com.samples.datasharetest.DataShare");
```
3. Create a **DataShareHelper** instance.
```ts
let dsHelper;
let abilityContext;
export default class MainAbility extends Ability {
export default class EntryAbility extends UIAbility {
onWindowStageCreate(windowStage) {
abilityContext = this.context;
dataShare.createDataShareHelper(abilityContext, dseUri, (err, data)=>{
......@@ -160,7 +203,7 @@ Examples are given below.
}
}
```
4. Use the APIs provided by **DataShareHelper** to access the services provided by the provider, for example, adding, deleting, modifying, and querying data.
```ts
......@@ -168,7 +211,7 @@ Examples are given below.
let valuesBucket = { "name": "ZhangSan", "age": 21, "isStudent": false, "Binary": new Uint8Array([1, 2, 3]) };
let updateBucket = { "name": "LiSi", "age": 18, "isStudent": true, "Binary": new Uint8Array([1, 2, 3]) };
let predicates = new dataSharePredicates.DataSharePredicates();
let valArray = new Array("*");
let valArray = ['*'];
// Insert a piece of data.
dsHelper.insert(dseUri, valuesBucket, (err, data) => {
console.log("dsHelper insert result: " + data);
......@@ -183,7 +226,6 @@ Examples are given below.
});
// Delete data.
dsHelper.delete(dseUri, predicates, (err, data) => {
console.log("dsHelper delete result: " + data);
console.log("dsHelper delete result: " + data);
});
```
en/application-dev/database/database-mdds-guidelines.md
浏览文件 @ 7e9154af
......@@ -14,12 +14,12 @@ For details about the APIs, see [Distributed KV Store](../reference/apis/js-apis
| API | Description |
| ------------------------------------------------------------ | ------------------------------------------------------------ |
| createKVManager(config: KVManagerConfig, callback: AsyncCallback&lt;KVManager&gt;): void<br>createKVManager(config: KVManagerConfig): Promise&lt;KVManager> | Creates a **KvManager** object for database management. |
| getKVStore&lt;TextendsKVStore&gt;(storeId: string, options: Options, callback: AsyncCallback&lt;T&gt;): void<br>getKVStore&lt;TextendsKVStore&gt;(storeId: string, options: Options): Promise&lt;T&gt; | Creates and obtains a KV store.|
| getKVStore&lt;T extends KVStore&gt;(storeId: string, options: Options, callback: AsyncCallback&lt;T&gt;): void<br>getKVStore&lt;T extends KVStore&gt;(storeId: string, options: Options): Promise&lt;T&gt; | Creates and obtains a KV store.|
| put(key: string, value: Uint8Array\|string\|number\|boolean, callback: AsyncCallback&lt;void&gt;): void<br>put(key: string, value: Uint8Array\|string\|number\|boolean): Promise&lt;void> | Inserts and updates data. |
| delete(key: string, callback: AsyncCallback&lt;void&gt;): void<br>delete(key: string): Promise&lt;void> | Deletes data. |
| get(key: string, callback: AsyncCallback&lt;Uint8Array\|string\|boolean\|number&gt;): void<br>get(key: string): Promise&lt;Uint8Array\|string\|boolean\|number> | Queries data. |
| get(key: string, callback: AsyncCallback&lt;Uint8Array\|string\|boolean\|number&gt;): void<br>get(key: string): Promise&lt;Uint8Array\|string\|boolean\|number> | Obtains data. |
| on(event: 'dataChange', type: SubscribeType, observer: Callback&lt;ChangeNotification&gt;): void<br>on(event: 'syncComplete', syncCallback: Callback&lt;Array&lt;[string,number]&gt;&gt;): void | Subscribes to data changes in the KV store. |
| sync(deviceIdList: string[], mode: SyncMode, allowedDelayMs?: number): void | Triggers database synchronization in manual mode. |
| sync(deviceIdList: string[], mode: SyncMode, delayMs?: number): void | Triggers database synchronization in manual mode. |
## How to Develop
......@@ -61,32 +61,32 @@ The following uses a single KV store as an example to describe the development p
context.requestPermissionsFromUser(['ohos.permission.DISTRIBUTED_DATASYNC'], 666).then((data) => {
console.info('success: ${data}');
}).catch((error) => {
console.info('failed: ${error}');
console.error('failed: ${error}');
})
}
grantPermission();
// Stage model
import Ability from '@ohos.application.Ability';
import UIAbility from '@ohos.app.ability.UIAbility';
let context = null;
function grantPermission() {
class MainAbility extends Ability {
onWindowStageCreate(windowStage) {
class EntryAbility extends UIAbility {
onWindowStageCreate(windowStage) {
let context = this.context;
}
}
}
let permissions = ['ohos.permission.DISTRIBUTED_DATASYNC'];
context.requestPermissionsFromUser(permissions).then((data) => {
function grantPermission() {
let permissions = ['ohos.permission.DISTRIBUTED_DATASYNC'];
context.requestPermissionsFromUser(permissions).then((data) => {
console.log('success: ${data}');
}).catch((error) => {
console.log('failed: ${error}');
});
}).catch((error) => {
console.error('failed: ${error}');
});
}
grantPermission();
```
......@@ -103,9 +103,9 @@ The following uses a single KV store as an example to describe the development p
let context = featureAbility.getContext();
// Obtain the context of the stage model.
import AbilityStage from '@ohos.application.Ability';
import UIAbility from '@ohos.app.ability.UIAbility';
let context = null;
class MainAbility extends AbilityStage{
class EntryAbility extends UIAbility {
onWindowStageCreate(windowStage){
context = this.context;
}
......@@ -119,7 +119,7 @@ The following uses a single KV store as an example to describe the development p
}
distributedKVStore.createKVManager(kvManagerConfig, function (err, manager) {
if (err) {
console.error(`Failed to create KVManager.code is ${err.code},message is ${err.message}`);
console.error(`Failed to create KVManager. code is ${err.code},message is ${err.message}`);
return;
}
console.log('Created KVManager successfully');
......
en/application-dev/database/database-preference-guidelines.md
浏览文件 @ 7e9154af
......@@ -113,10 +113,10 @@ You can use the following APIs to delete a **Preferences** instance or data file
```ts
// Obtain the context.
import Ability from '@ohos.application.Ability'
import UIAbility from '@ohos.app.ability.UIAbility'
let context = null;
let preferences = null;
export default class MainAbility extends Ability {
export default class EntryAbility extends UIAbility {
onWindowStageCreate(windowStage){
context = this.context;
}
......@@ -159,7 +159,7 @@ You can use the following APIs to delete a **Preferences** instance or data file
5. Store data persistently.
Use **flush()** to flush data from the **Preferences** instance to its file.
Use **preferences.flush()** to flush data from the **Preferences** instance to its file.
```js
preferences.flush();
......@@ -186,7 +186,7 @@ You can use the following APIs to delete a **Preferences** instance or data file
console.info("Failed to flush data. Cause: " + err);
return;
}
console.info("Flushed data successfully."); // The observer will be called.
console.info("Flushed data successfully."); // The observer will be called.
})
})
```
......@@ -200,6 +200,6 @@ You can use the following APIs to delete a **Preferences** instance or data file
proDelete.then(() => {
console.info("Deleted data successfully.");
}).catch((err) => {
console.info("Failed to delete data. Cause: " + err);
console.info("Failed to delete data. Cause: " + err);
})
```
en/application-dev/reference/apis/js-apis-data-dataShare.md
浏览文件 @ 7e9154af
# @ohos.data.dataShare (DataShare)
# @ohos.data.dataShare (Data Sharing)
The **DataShare** module allows an application to manage its own data and share data with other applications on the same device.
......@@ -37,18 +37,12 @@ Example:
**com.samples.datasharetest.DataShare** is the data share identifier, and **DB00/TBL00** is the resource path.
## dataShare.createDataShareHelper
createDataShareHelper(context: Context, uri: string, callback: AsyncCallback&lt;DataShareHelper&gt;): void
Creates a **DataShareHelper** instance. This API uses an asynchronous callback to return the result.
Observe the following when using this API:
- If an application running in the background needs to call this API to access **DataShareExtension**, it must have the **ohos.permission.START_ABILITIES_FROM_BACKGROUND** permission.
- If **visible** of the target **DataShareExtension** is **false** in cross-application scenarios, the caller must have the **ohos.permission.START_INVISIBLE_ABILITY** permission.
- For details about the startup rules for the components in the stage model, see [Component Startup Rules (Stage Model)](../../application-models/component-startup-rules.md).
**System capability**: SystemCapability.DistributedDataManager.DataShare.Consumer
**Parameters**
......@@ -70,7 +64,7 @@ For details about the error codes, see [DataShare Error Codes](../errorcodes/err
**Example**
```ts
import UIAbility from '@ohos.app.ability.UIAbility';
import UIAbility from '@ohos.app.ability.UIAbility'
let uri = ("datashare:///com.samples.datasharetest.DataShare");
let dataShareHelper;
......@@ -94,11 +88,6 @@ createDataShareHelper(context: Context, uri: string): Promise&lt;DataShareHelper
Creates a **DataShareHelper** instance. This API uses a promise to return the result.
Observe the following when using this API:
- If an application running in the background needs to call this API to access **DataShareExtension**, it must have the **ohos.permission.START_ABILITIES_FROM_BACKGROUND** permission.
- If **visible** of the target **DataShareExtension** is **false** in cross-application scenarios, the caller must have the **ohos.permission.START_INVISIBLE_ABILITY** permission.
- For details about the startup rules for the components in the stage model, see [Component Startup Rules (Stage Model)](../../application-models/component-startup-rules.md).
**System capability**: SystemCapability.DistributedDataManager.DataShare.Consumer
**Parameters**
......@@ -125,7 +114,7 @@ For details about the error codes, see [DataShare Error Codes](../errorcodes/err
**Example**
```ts
import UIAbility from '@ohos.app.ability.UIAbility';
import UIAbility from '@ohos.app.ability.UIAbility'
let uri = ("datashare:///com.samples.datasharetest.DataShare");
let dataShareHelper;
......@@ -164,8 +153,7 @@ Subscribes to changes of the specified data. After an observer is registered, th
**Example**
```ts
import UIAbility from '@ohos.app.ability.UIAbility';
import UIAbility from '@ohos.app.ability.UIAbility'
function onCallback() {
console.info("**** Observer on callback ****");
}
......@@ -187,13 +175,12 @@ Unsubscribes from the changes of the specified data. This API uses an asynchrono
| -------- | -------------------- | ---- | ------------------------ |
| type | string | Yes | Event type to unsubscribe from. The value is **dataChange**, which indicates data change events.|
| uri | string | Yes | URI of the data.|
| callback | AsyncCallback&lt;void&gt; | No | Callback used to return the result. If the operation is successful, **err** is **undefined**. Otherwise, **err** is an error object.|
| callback | AsyncCallback&lt;void&gt; | No | Callback invoked to return the result. If the operation is successful, **err** is **undefined**. Otherwise, **err** is an error object.|
**Example**
```ts
import UIAbility from '@ohos.app.ability.UIAbility';
import UIAbility from '@ohos.app.ability.UIAbility'
function offCallback() {
console.info("**** Observer off callback ****");
}
......@@ -220,8 +207,7 @@ Inserts a single data record into the database. This API uses an asynchronous ca
**Example**
```ts
import UIAbility from '@ohos.app.ability.UIAbility';
import UIAbility from '@ohos.app.ability.UIAbility'
let uri = ("datashare:///com.samples.datasharetest.DataShare");
const valueBucket = {
"name": "rose",
......@@ -265,8 +251,7 @@ Inserts a single data record into the database. This API uses a promise to retur
**Example**
```ts
import UIAbility from '@ohos.app.ability.UIAbility';
import UIAbility from '@ohos.app.ability.UIAbility'
let uri = ("datashare:///com.samples.datasharetest.DataShare");
const valueBucket = {
"name": "rose1",
......@@ -303,8 +288,8 @@ Deletes one or more data records from the database. This API uses an asynchronou
**Example**
```ts
import UIAbility from '@ohos.app.ability.UIAbility';
import dataSharePredicates from '@ohos.data.dataSharePredicates';
import UIAbility from '@ohos.app.ability.UIAbility'
import dataSharePredicates from '@ohos.data.dataSharePredicates'
let uri = ("datashare:///com.samples.datasharetest.DataShare");
let da = new dataSharePredicates.DataSharePredicates();
......@@ -346,8 +331,8 @@ Deletes one or more data records from the database. This API uses a promise to r
**Example**
```ts
import UIAbility from '@ohos.app.ability.UIAbility';
import dataSharePredicates from '@ohos.data.dataSharePredicates';
import UIAbility from '@ohos.app.ability.UIAbility'
import dataSharePredicates from '@ohos.data.dataSharePredicates'
let uri = ("datashare:///com.samples.datasharetest.DataShare");
let da = new dataSharePredicates.DataSharePredicates();
......@@ -383,8 +368,8 @@ Queries data in the database. This API uses an asynchronous callback to return t
**Example**
```ts
import UIAbility from '@ohos.app.ability.UIAbility';
import dataSharePredicates from '@ohos.data.dataSharePredicates';
import UIAbility from '@ohos.app.ability.UIAbility'
import dataSharePredicates from '@ohos.data.dataSharePredicates'
let uri = ("datashare:///com.samples.datasharetest.DataShare");
let columns = ["*"];
......@@ -428,8 +413,8 @@ Queries data in the database. This API uses a promise to return the result.
**Example**
```ts
import UIAbility from '@ohos.app.ability.UIAbility';
import dataSharePredicates from '@ohos.data.dataSharePredicates';
import UIAbility from '@ohos.app.ability.UIAbility'
import dataSharePredicates from '@ohos.data.dataSharePredicates'
let uri = ("datashare:///com.samples.datasharetest.DataShare");
let columns = ["*"];
......@@ -466,8 +451,8 @@ Updates data in the database. This API uses an asynchronous callback to return t
**Example**
```ts
import UIAbility from '@ohos.app.ability.UIAbility';
import dataSharePredicates from '@ohos.data.dataSharePredicates';
import UIAbility from '@ohos.app.ability.UIAbility'
import dataSharePredicates from '@ohos.data.dataSharePredicates'
let uri = ("datashare:///com.samples.datasharetest.DataShare");
let da = new dataSharePredicates.DataSharePredicates();
......@@ -516,8 +501,8 @@ Updates data in the database. This API uses a promise to return the result.
**Example**
```ts
import UIAbility from '@ohos.app.ability.UIAbility';
import dataSharePredicates from '@ohos.data.dataSharePredicates';
import UIAbility from '@ohos.app.ability.UIAbility'
import dataSharePredicates from '@ohos.data.dataSharePredicates'
let uri = ("datashare:///com.samples.datasharetest.DataShare");
let da = new dataSharePredicates.DataSharePredicates();
......@@ -558,8 +543,7 @@ Batch inserts data into the database. This API uses an asynchronous callback to
**Example**
```ts
import UIAbility from '@ohos.app.ability.UIAbility';
import UIAbility from '@ohos.app.ability.UIAbility'
let uri = ("datashare:///com.samples.datasharetest.DataShare");
let vbs = new Array({"name": "roe11", "age": 21, "salary": 20.5,},
{"name": "roe12", "age": 21, "salary": 20.5,},
......@@ -601,8 +585,7 @@ Batch inserts data into the database. This API uses a promise to return the resu
**Example**
```ts
import UIAbility from '@ohos.app.ability.UIAbility';
import UIAbility from '@ohos.app.ability.UIAbility'
let uri = ("datashare:///com.samples.datasharetest.DataShare");
let vbs = new Array({"name": "roe11", "age": 21, "salary": 20.5,},
{"name": "roe12", "age": 21, "salary": 20.5,},
......@@ -636,8 +619,7 @@ Normalizes a **DataShare** URI. The **DataShare** URI can be used only by the lo
**Example**
```ts
import UIAbility from '@ohos.app.ability.UIAbility';
import UIAbility from '@ohos.app.ability.UIAbility'
let uri = ("datashare:///com.samples.datasharetest.DataShare");
dataShareHelper.normalizeUri(uri, (err, data) => {
if (err != undefined) {
......@@ -671,8 +653,7 @@ Normalizes a **DataShare** URI. The **DataShare** URI can be used only by the lo
**Example**
```ts
import UIAbility from '@ohos.app.ability.UIAbility';
import UIAbility from '@ohos.app.ability.UIAbility'
let uri = ("datashare:///com.samples.datasharetest.DataShare");
dataShareHelper.normalizeUri(uri).then((data) => {
console.log("normalizeUri = " + data);
......@@ -699,8 +680,7 @@ Denormalizes a URI. This API uses an asynchronous callback to return the result.
**Example**
```ts
import UIAbility from '@ohos.app.ability.UIAbility';
import UIAbility from '@ohos.app.ability.UIAbility'
let uri = ("datashare:///com.samples.datasharetest.DataShare");
dataShareHelper.denormalizeUri(uri, (err, data) => {
if (err != undefined) {
......@@ -734,8 +714,7 @@ Denormalizes a URI. This API uses a promise to return the result.
**Example**
```ts
import UIAbility from '@ohos.app.ability.UIAbility';
import UIAbility from '@ohos.app.ability.UIAbility'
let uri = ("datashare:///com.samples.datasharetest.DataShare");
dataShareHelper.denormalizeUri(uri).then((data) => {
console.log("denormalizeUri = " + data);
......@@ -762,8 +741,7 @@ Notifies the registered observer of data changes. This API uses an asynchronous
**Example**
```ts
import UIAbility from '@ohos.app.ability.UIAbility';
import UIAbility from '@ohos.app.ability.UIAbility'
let uri = ("datashare:///com.samples.datasharetest.DataShare");
dataShareHelper.notifyChange(uri, () => {
console.log("***** notifyChange *****");
......@@ -793,8 +771,7 @@ Notifies the registered observer of data changes. This API uses a promise to ret
**Example**
```ts
import UIAbility from '@ohos.app.ability.UIAbility';
import UIAbility from '@ohos.app.ability.UIAbility'
let uri = ("datashare:///com.samples.datasharetest.DataShare");
dataShareHelper.notifyChange(uri);
```
en/application-dev/reference/apis/js-apis-data-preferences.md
浏览文件 @ 7e9154af
......@@ -38,7 +38,7 @@ Obtains a **Preferences** instance. This API uses an asynchronous callback to re
| Name | Type | Mandatory| Description |
| -------- | ------------------------------------------------ | ---- | ------------------------------------------------------------ |
| context | Context | Yes | Application context.<br>For the application context of the FA model, see [Context](js-apis-inner-app-context.md).<br>For the application context of the stage model, see [Context](js-apis-ability-context.md). |
| context | Context | Yes | Application context.<br>For details about the application context of the FA model, see [Context](js-apis-inner-app-context.md).<br>For details about the application context of the stage model, see [Context](js-apis-ability-context.md). |
| name | string | Yes | Name of the **Preferences** instance.|
| callback | AsyncCallback&lt;[Preferences](#preferences)&gt; | Yes | Callback invoked to return the result. If the operation is successful, **err** is **undefined** and **object** is the **Preferences** instance obtained. Otherwise, **err** is an error code.|
......@@ -69,9 +69,9 @@ Stage model:
```ts
// Obtain the context.
import Ability from '@ohos.application.Ability';
import UIAbility from '@ohos.app.ability.UIAbility';
let context = null;
class MainAbility extends Ability{
class EntryAbility extends UIAbility {
onWindowStageCreate(windowStage){
context = this.context;
}
......@@ -103,7 +103,7 @@ Obtains a **Preferences** instance. This API uses a promise to return the result
| Name | Type | Mandatory| Description |
| ------- | ------------------------------------- | ---- | ----------------------- |
| context | Context | Yes | Application context.<br>For the application context of the FA model, see [Context](js-apis-inner-app-context.md).<br>For the application context of the stage model, see [Context](js-apis-ability-context.md). |
| context | Context | Yes | Application context.<br>For details about the application context of the FA model, see [Context](js-apis-inner-app-context.md).<br>For details about the application context of the stage model, see [Context](js-apis-ability-context.md). |
| name | string | Yes | Name of the **Preferences** instance.|
**Return value**
......@@ -139,9 +139,9 @@ Stage model:
```ts
// Obtain the context.
import Ability from '@ohos.application.Ability';
import UIAbility from '@ohos.app.ability.UIAbility';
let context = null;
class MainAbility extends Ability{
class EntryAbility extends UIAbility {
onWindowStageCreate(windowStage){
context = this.context;
}
......@@ -177,7 +177,7 @@ The deleted **Preferences** instance cannot be used for data operations. Otherwi
| Name | Type | Mandatory| Description |
| -------- | ------------------------------------- | ---- | ---------------------------------------------------- |
| context | Context | Yes | Application context.<br>For the application context of the FA model, see [Context](js-apis-inner-app-context.md).<br>For the application context of the stage model, see [Context](js-apis-ability-context.md). |
| context | Context | Yes | Application context.<br>For details about the application context of the FA model, see [Context](js-apis-inner-app-context.md).<br>For details about the application context of the stage model, see [Context](js-apis-ability-context.md). |
| name | string | Yes | Name of the **Preferences** instance to delete. |
| callback | AsyncCallback&lt;void&gt; | Yes | Callback invoked to return the result. If the operation is successful, **err** is **undefined**. Otherwise, **err** is an error code.|
......@@ -215,9 +215,9 @@ Stage model:
```ts
// Obtain the context.
import Ability from '@ohos.application.Ability';
import UIAbility from '@ohos.app.ability.UIAbility';
let context = null;
class MainAbility extends Ability{
class EntryAbility extends UIAbility {
onWindowStageCreate(windowStage){
context = this.context;
}
......@@ -252,7 +252,7 @@ The deleted **Preferences** instance cannot be used for data operations. Otherwi
| Name | Type | Mandatory| Description |
| ------- | ------------------------------------- | ---- | ----------------------- |
| context | Context | Yes | Application context.<br>For the application context of the FA model, see [Context](js-apis-inner-app-context.md).<br>For the application context of the stage model, see [Context](js-apis-ability-context.md). |
| context | Context | Yes | Application context.<br>For details about the application context of the FA model, see [Context](js-apis-inner-app-context.md).<br>For details about the application context of the stage model, see [Context](js-apis-ability-context.md). |
| name | string | Yes | Name of the **Preferences** instance to delete.|
**Return value**
......@@ -294,9 +294,9 @@ Stage model:
```ts
// Obtain the context.
import Ability from '@ohos.application.Ability';
import UIAbility from '@ohos.app.ability.UIAbility';
let context = null;
class MainAbility extends Ability{
class EntryAbility extends UIAbility {
onWindowStageCreate(windowStage){
context = this.context;
}
......@@ -328,7 +328,7 @@ The removed **Preferences** instance cannot be used for data operations. Otherwi
| Name | Type | Mandatory| Description |
| -------- | ------------------------------------- | ---- | ---------------------------------------------------- |
| context | Context | Yes | Application context.<br>For the application context of the FA model, see [Context](js-apis-inner-app-context.md).<br>For the application context of the stage model, see [Context](js-apis-ability-context.md). |
| context | Context | Yes | Application context.<br>For details about the application context of the FA model, see [Context](js-apis-inner-app-context.md).<br>For details about the application context of the stage model, see [Context](js-apis-ability-context.md). |
| name | string | Yes | Name of the **Preferences** instance to remove. |
| callback | AsyncCallback&lt;void&gt; | Yes | Callback invoked to return the result. If the operation is successful, **err** is **undefined**. Otherwise, **err** is an error code.|
......@@ -358,9 +358,9 @@ Stage model:
```ts
// Obtain the context.
import Ability from '@ohos.application.Ability';
import UIAbility from '@ohos.app.ability.UIAbility';
let context = null;
class MainAbility extends Ability{
class EntryAbility extends UIAbility {
onWindowStageCreate(windowStage){
context = this.context;
}
......@@ -394,7 +394,7 @@ The removed **Preferences** instance cannot be used for data operations. Otherwi
| Name | Type | Mandatory| Description |
| ------- | ------------------------------------- | ---- | ----------------------- |
| context | Context | Yes | Application context.<br>For the application context of the FA model, see [Context](js-apis-inner-app-context.md).<br>For the application context of the stage model, see [Context](js-apis-ability-context.md). |
| context | Context | Yes | Application context.<br>For details about the application context of the FA model, see [Context](js-apis-inner-app-context.md).<br>For details about the application context of the stage model, see [Context](js-apis-ability-context.md). |
| name | string | Yes | Name of the **Preferences** instance to remove.|
**Return value**
......@@ -428,9 +428,9 @@ Stage model:
```ts
// Obtain the context.
import Ability from '@ohos.application.Ability';
import UIAbility from '@ohos.app.ability.UIAbility';
let context = null;
class MainAbility extends Ability{
class EntryAbility extends UIAbility {
onWindowStageCreate(windowStage){
context = this.context;
}
......@@ -662,7 +662,7 @@ try {
has(key: string, callback: AsyncCallback&lt;boolean&gt;): void
Checks whether this **Preferences** instance contains a KV pair with the given key. This API uses an asynchronous callback to return the result..
Checks whether this **Preferences** instance contains a KV pair with the given key. This API uses an asynchronous callback to return the result.
**System capability**: SystemCapability.DistributedDataManager.Preferences.Core
......@@ -698,7 +698,7 @@ try {
has(key: string): Promise&lt;boolean&gt;
Checks whether this **Preferences** instance contains a KV pair with the given key. This API uses a promise to return the result..
Checks whether this **Preferences** instance contains a KV pair with the given key. This API uses a promise to return the result.
**System capability**: SystemCapability.DistributedDataManager.Preferences.Core
......@@ -987,7 +987,7 @@ Unsubscribes from data changes.
| Name | Type | Mandatory| Description |
| -------- | -------------------------------- | ---- | ------------------------------------------ |
| type | string | Yes | Event type to unsubscribe from. The value **change** indicates data change events. |
| callback | Callback&lt;{ key : string }&gt; | No | Callback to unregister. If this parameter is left blank, the callbacks used to subscribing to all data changes will be unregistered.|
| callback | Callback&lt;{ key : string }&gt; | No | Callback to unregister. If this parameter is left blank, all callbacks for data changes will be unregistered. |
**Example**
......
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