diff --git a/zh-cn/application-dev/database/database-distributedobject-guidelines.md b/zh-cn/application-dev/database/database-distributedobject-guidelines.md
index 8a8d499bb5cda3b850eb72023fc784f2b485f090..ebce36fce4e9e5f14ae0c128503e0fc9e1ff5eac 100644
--- a/zh-cn/application-dev/database/database-distributedobject-guidelines.md
+++ b/zh-cn/application-dev/database/database-distributedobject-guidelines.md
@@ -142,7 +142,7 @@
    function grantPermission() {
      let permissions = ['ohos.permission.DISTRIBUTED_DATASYNC'];
      context.requestPermissionsFromUser(permissions).then((data) => {
-       console.log('success: ${data}');
+       console.info('success: ${data}');
      }).catch((error) => {
        console.error('failed: ${error}');
      });
diff --git a/zh-cn/application-dev/database/database-preference-guidelines.md b/zh-cn/application-dev/database/database-preference-guidelines.md
index e2fdd2e055e4b8cd6340f6c67f4863be99b85bab..2ce239c7d37247f28afd1fc979cbd1583c1be6f9 100644
--- a/zh-cn/application-dev/database/database-preference-guidelines.md
+++ b/zh-cn/application-dev/database/database-preference-guidelines.md
@@ -113,22 +113,20 @@
 
    ```ts
    // 获取context
-   import UIAbility from '@ohos.app.ability.UIAbility'
-   let context = null;
+   import UIAbility from '@ohos.app.ability.UIAbility';
    let preferences = null;
    export default class EntryAbility extends UIAbility {
-       onWindowStageCreate(windowStage){
-           context = this.context;
+       onWindowStageCreate(windowStage) {
+           let promise = data_preferences.getPreferences(this.context, 'mystore');
+            promise.then((pref) => {
+                preferences = pref;
+            }).catch((err) => {
+                console.info("Failed to get preferences.");
+            })
        }
    }
    
-   let promise = data_preferences.getPreferences(context, 'mystore');
    
-   promise.then((pref) => {
-       preferences = pref;
-   }).catch((err) => {
-       console.info("Failed to get preferences.");
-   })
    ```
 
 3. 存入数据。
diff --git a/zh-cn/application-dev/reference/apis/js-apis-data-distributedobject.md b/zh-cn/application-dev/reference/apis/js-apis-data-distributedobject.md
index a0e388b6711bf468a4a282cc28fef3df7b0e9249..780ae2299547437e0ec3b8aab8a88bc582022ce6 100644
--- a/zh-cn/application-dev/reference/apis/js-apis-data-distributedobject.md
+++ b/zh-cn/application-dev/reference/apis/js-apis-data-distributedobject.md
@@ -15,7 +15,7 @@ import distributedObject from '@ohos.data.distributedDataObject';
 
 ## distributedObject.create<sup>9+</sup>
 
-create(context: Context, source: object): DistributedObjectV9
+create(context: Context, source: object): DataObject
 
 创建一个分布式数据对象。
 
@@ -32,7 +32,7 @@ create(context: Context, source: object): DistributedObjectV9
 
 | 类型 | 说明 |
 | -------- | -------- |
-| [DistributedObjectV9](#distributedobjectv9) | 创建完成的分布式数据对象。 |
+| [DataObject](#dataobject) | 创建完成的分布式数据对象。 |
 
 **示例：**
 
@@ -44,7 +44,7 @@ import distributedObject from '@ohos.data.distributedDataObject';
 import featureAbility from '@ohos.ability.featureAbility';
 // 获取context
 let context = featureAbility.getContext();
-// 创建对象，该对象包含4个属性类型，string,number,boolean和Object
+// 创建对象，该对象包含4个属性类型：string、number、boolean和Object
 let g_object = distributedObject.create(context, {name:"Amy", age:18, isVis:false, parent:{mother:"jack mom",father:"jack Dad"}});
 ```
 
@@ -54,15 +54,15 @@ Stage模型示例：
 // 导入模块
 import distributedObject from '@ohos.data.distributedDataObject';
 import UIAbility from '@ohos.app.ability.UIAbility';
-// 获取context
-let context;
+
+let g_object = null;
+
 class EntryAbility extends UIAbility {
     onWindowStageCreate(windowStage){
-        context = this.context
+        // 创建对象，该对象包含4个属性类型：string、number、boolean和Object
+        g_object = distributedObject.create(this.context, {name:"Amy", age:18, isVis:false, parent:{mother:"jack mom",father:"jack Dad"}});
     }
 }
-// 创建对象，该对象包含4个属性类型，string,number,boolean和Object
-let g_object = distributedObject.create(context, {name:"Amy", age:18, isVis:false, parent:{mother:"jack mom",father:"jack Dad"}});
 ```
 
 ## distributedObject.genSessionId
@@ -108,9 +108,9 @@ revokeSave接口回调信息。
 | -------- | -------- | -------- | -------- |
 | sessionId | string | 是 | 多设备协同的唯一标识。 |
 
-## DistributedObjectV9
+## DataObject
 
-表示一个分布式数据对象。
+表示一个分布式数据对象。在使用以下接口前，需调用[create()](#distributedobjectcreate9)获取DataObject对象。
 
 ### setSessionId<sup>9+</sup>
 
@@ -139,35 +139,10 @@ setSessionId(sessionId: string, callback: AsyncCallback&lt;void&gt;): void
 
 **示例：**
 
-FA模型示例
-
 ```js
-import distributedObject from '@ohos.data.distributedDataObject';
-import featureAbility from '@ohos.ability.featureAbility';
-// 获取context
-let context = featureAbility.getContext();
-let g_object = distributedObject.create(context, {name:"Amy", age:18, isVis:false, parent:{mother:"jack mom",father:"jack Dad"}});
-// g_object加入分布式组网
-g_object.setSessionId(distributedObject.genSessionId(), ()=>{
-    console.log("join session");
-});
-```
-Stage模型示例
-
-```ts
-import distributedObject from '@ohos.data.distributedDataObject';
-import UIAbility from '@ohos.app.ability.UIAbility';
-// 获取context
-let context;
-class EntryAbility extends UIAbility {
-    onWindowStageCreate(windowStage){
-        context = this.context
-    }
-}
-let g_object = distributedObject.create(context, {name:"Amy", age:18, isVis:false, parent:{mother:"jack mom",father:"jack Dad"}});
 // g_object加入分布式组网
 g_object.setSessionId(distributedObject.genSessionId(), ()=>{
-    console.log("join session");
+    console.info("join session");
 });
 ```
 
@@ -197,43 +172,14 @@ setSessionId(callback: AsyncCallback&lt;void&gt;): void
 
 **示例：**
 
-FA模型示例
-
 ```js
-import distributedObject from '@ohos.data.distributedDataObject';
-import featureAbility from '@ohos.ability.featureAbility';
-// 获取context
-let context = featureAbility.getContext();
-let g_object = distributedObject.create(context, {name:"Amy", age:18, isVis:false, parent:{mother:"jack mom",father:"jack Dad"}});
 // g_object加入分布式组网
 g_object.setSessionId(distributedObject.genSessionId(), ()=>{
-    console.log("join session");
+    console.info("join session");
 });
 // 退出分布式组网
 g_object.setSessionId(() => {
-    console.log("leave all lession.");
-});
-```
-Stage模型示例
-
-```ts
-import distributedObject from '@ohos.data.distributedDataObject';
-import UIAbility from '@ohos.app.ability.UIAbility';
-// 获取context
-let context;
-class EntryAbility extends UIAbility {
-    onWindowStageCreate(windowStage){
-        context = this.context
-    }
-}
-let g_object = distributedObject.create(context, {name:"Amy", age:18, isVis:false, parent:{mother:"jack mom",father:"jack Dad"}});
-// g_object加入分布式组网
-g_object.setSessionId(distributedObject.genSessionId(), ()=>{
-    console.log("join session");
-});
-// 退出分布式组网
-g_object.setSessionId(() => {
-    console.log("leave all lession.");
+    console.info("leave all lession.");
 });
 ```
 
@@ -269,40 +215,7 @@ setSessionId(sessionId?: string): Promise&lt;void&gt;
 
 **示例：**
 
-FA模型示例
-
 ```js
-import distributedObject from '@ohos.data.distributedDataObject';
-import featureAbility from '@ohos.ability.featureAbility';
-// 获取context
-let context = featureAbility.getContext();
-let g_object = distributedObject.create(context, {name:"Amy", age:18, isVis:false, parent:{mother:"jack mom",father:"jack Dad"}});
-// g_object加入分布式组网
-g_object.setSessionId(distributedObject.genSessionId()).then (()=>{
-    console.log("join session.");
-    }).catch((error)=>{
-        console.info("error:" + error.code + error.message);
-});
-// 退出分布式组网
-g_object.setSessionId().then (()=>{
-    console.log("leave all lession.");
-    }).catch((error)=>{
-        console.info("error:" + error.code + error.message);
-});
-```
-Stage模型示例
-
-```ts
-import distributedObject from '@ohos.data.distributedDataObject';
-import UIAbility from '@ohos.app.ability.UIAbility';
-// 获取context
-let context;
-class EntryAbility extends UIAbility {
-    onWindowStageCreate(windowStage){
-        context = this.context
-    }
-}
-let g_object = distributedObject.create(context, {name:"Amy", age:18, isVis:false, parent:{mother:"jack mom",father:"jack Dad"}});
 // g_object加入分布式组网
 g_object.setSessionId(distributedObject.genSessionId()).then (()=>{
     console.info("join session.");
@@ -311,7 +224,7 @@ g_object.setSessionId(distributedObject.genSessionId()).then (()=>{
 });
 // 退出分布式组网
 g_object.setSessionId().then (()=>{
-    console.log("leave all lession.");
+    console.info("leave all lession.");
     }).catch((error)=>{
         console.info("error:" + error.code + error.message);
 });
@@ -334,38 +247,7 @@ on(type: 'change', callback: Callback<{ sessionId: string, fields: Array&lt;stri
 
 **示例：**
 
-FA模型示例
-
 ```js
-import distributedObject from '@ohos.data.distributedDataObject';
-import featureAbility from '@ohos.ability.featureAbility';
-// 获取context
-let context = featureAbility.getContext();
-let g_object = distributedObject.create(context, {name:"Amy", age:18, isVis:false, parent:{mother:"jack mom",father:"jack Dad"}});
-globalThis.changeCallback = (sessionId, changeData) => {
-    console.info("change" + sessionId);
-    if (changeData != null && changeData != undefined) {
-        changeData.forEach(element => {
-        console.info("changed !" + element + " " + g_object[element]);
-        });
-    }
-}
-g_object.on("change", globalThis.changeCallback);
-```
-
-Stage模型示例
-
-```ts
-import distributedObject from '@ohos.data.distributedDataObject';
-import UIAbility from '@ohos.app.ability.UIAbility';
-// 获取context
-let context;
-class EntryAbility extends UIAbility {
-    onWindowStageCreate(windowStage){
-        context = this.context
-    }
-}
-let g_object = distributedObject.create(context, {name:"Amy", age:18, isVis:false, parent:{mother:"jack mom",father:"jack Dad"}});
 globalThis.changeCallback = (sessionId, changeData) => {
     console.info("change" + sessionId);
     if (changeData != null && changeData != undefined) {
@@ -395,33 +277,7 @@ off(type: 'change', callback?: Callback<{ sessionId: string, fields: Array&lt;st
 
 **示例：**
 
-FA模型示例
-
 ```js
-import distributedObject from '@ohos.data.distributedDataObject';
-import featureAbility from '@ohos.ability.featureAbility';
-// 获取context
-let context = featureAbility.getContext();
-let g_object = distributedObject.create(context, {name:"Amy", age:18, isVis:false, parent:{mother:"jack mom",father:"jack Dad"}});
-// 删除数据变更回调changeCallback
-g_object.off("change", globalThis.changeCallback);
-// 删除所有的数据变更回调
-g_object.off("change");
-```
-
-Stage模型示例
-
-```ts
-import distributedObject from '@ohos.data.distributedDataObject';
-import UIAbility from '@ohos.app.ability.UIAbility';
-// 获取context
-let context;
-class EntryAbility extends UIAbility {
-    onWindowStageCreate(windowStage){
-        context = this.context
-    }
-}
-let g_object = distributedObject.create(context, {name:"Amy", age:18, isVis:false, parent:{mother:"jack mom",father:"jack Dad"}});
 // 删除数据变更回调changeCallback
 g_object.off("change", globalThis.changeCallback);
 // 删除所有的数据变更回调
@@ -445,36 +301,10 @@ on(type: 'status', callback: Callback<{ sessionId: string, networkId: string, st
 
 **示例：**
 
-FA模型示例
-
 ```js
-import distributedObject from '@ohos.data.distributedDataObject';
-import featureAbility from '@ohos.ability.featureAbility';
-// 获取context
-let context = featureAbility.getContext();
 globalThis.statusCallback = (sessionId, networkId, status) => {
     globalThis.response += "status changed " + sessionId + " " + status + " " + networkId;
 }
-let g_object = distributedObject.create(context, {name:"Amy", age:18, isVis:false, parent:{mother:"jack mom",father:"jack Dad"}});
-g_object.on("status", globalThis.statusCallback);
-```
-
-Stage模型示例
-
-```ts
-import distributedObject from '@ohos.data.distributedDataObject';
-import UIAbility from '@ohos.app.ability.UIAbility';
-// 获取context
-let context;
-class EntryAbility extends UIAbility {
-    onWindowStageCreate(windowStage){
-        context = this.context
-    }
-}
-globalThis.statusCallback = (sessionId, networkId, status) => {
-    globalThis.response += "status changed " + sessionId + " " + status + " " + networkId;
-}
-let g_object = distributedObject.create(context, {name:"Amy", age:18, isVis:false, parent:{mother:"jack mom",father:"jack Dad"}});
 g_object.on("status", globalThis.statusCallback);
 ```
 
@@ -496,36 +326,7 @@ off(type: 'status', callback?: Callback<{ sessionId: string, deviceId: string, s
 
 **示例：**
 
-FA模型示例
-
 ```js
-import distributedObject from '@ohos.data.distributedDataObject'; 
-import featureAbility from '@ohos.ability.featureAbility';
-// 获取context
-let context = featureAbility.getContext();
-let g_object = distributedObject.create(context, {name:"Amy", age:18, isVis:false, parent:{mother:"jack mom",father:"jack Dad"}});
-globalThis.statusCallback = (sessionId, networkId, status) => {
-    globalThis.response += "status changed " + sessionId + " " + status + " " + networkId;
-}
-// 删除上下线回调changeCallback
-g_object.off("status",globalThis.statusCallback);
-// 删除所有的上下线回调
-g_object.off("status");
-```
-
-Stage模型示例
-
-```ts
-import distributedObject from '@ohos.data.distributedDataObject'; 
-import UIAbility from '@ohos.app.ability.UIAbility';
-// 获取context
-let context;
-class EntryAbility extends UIAbility {
-    onWindowStageCreate(windowStage){
-        context = this.context
-    }
-}
-let g_object = distributedObject.create(context, {name:"Amy", age:18, isVis:false, parent:{mother:"jack mom",father:"jack Dad"}});
 globalThis.statusCallback = (sessionId, networkId, status) => {
     globalThis.response += "status changed " + sessionId + " " + status + " " + networkId;
 }
@@ -560,37 +361,10 @@ save(deviceId: string, callback: AsyncCallback&lt;SaveSuccessResponse&gt;): void
 
 **示例：**
 
-FA模型示例
 ```ts
-import distributedObject from '@ohos.data.distributedDataObject';
-import featureAbility from '@ohos.ability.featureAbility';
-// 获取context
-let context = featureAbility.getContext();
-let g_object = distributedObject.create(context, {name:"Amy", age:18, isVis:false});
 g_object.setSessionId("123456");
 g_object.save("local", (result) => {
-    console.log("save callback");
-    console.info("save sessionId: " + result.sessionId);
-    console.info("save version: " + result.version);
-    console.info("save deviceId:  " + result.deviceId);
-});
-```
-
-Stage模型示例
-```ts
-import distributedObject from '@ohos.data.distributedDataObject';
-import UIAbility from '@ohos.app.ability.UIAbility';
-// 获取context
-let context;
-class EntryAbility extends UIAbility {
-    onWindowStageCreate(windowStage){
-        context = this.context
-    }
-}
-let g_object = distributedObject.create(context, {name:"Amy", age:18, isVis:false});
-g_object.setSessionId("123456");
-g_object.save("local", (result) => {
-    console.log("save callback");
+    console.info("save callback");
     console.info("save sessionId: " + result.sessionId);
     console.info("save version: " + result.version);
     console.info("save deviceId:  " + result.deviceId);
@@ -627,40 +401,10 @@ save(deviceId: string): Promise&lt;SaveSuccessResponse&gt;
 
 **示例：**
 
-FA模型示例
-
 ```js
-import distributedObject from '@ohos.data.distributedDataObject';
-import featureAbility from '@ohos.ability.featureAbility';
-// 获取context
-let context = featureAbility.getContext();
-let g_object = distributedObject.create(context,{name:"Amy", age:18, isVis:false});
 g_object.setSessionId("123456");
 g_object.save("local").then((result) => {
-    console.log("save callback");
-    console.info("save sessionId " + result.sessionId);
-    console.info("save version " + result.version);
-    console.info("save deviceId " + result.deviceId);
-}, () => {
-    console.error("save failed");
-});
-```
-Stage模型示例
-
-```js
-import distributedObject from '@ohos.data.distributedDataObject';
-import UIAbility from '@ohos.app.ability.UIAbility';
-// 获取context
-let context;
-class EntryAbility extends UIAbility {
-    onWindowStageCreate(windowStage){
-        context = this.context
-    }
-}
-let g_object = distributedObject.create(context,{name:"Amy", age:18, isVis:false});
-g_object.setSessionId("123456");
-g_object.save("local").then((result) => {
-    console.log("save callback");
+    console.info("save callback");
     console.info("save sessionId " + result.sessionId);
     console.info("save version " + result.version);
     console.info("save deviceId " + result.deviceId);
@@ -688,54 +432,19 @@ revokeSave(callback: AsyncCallback&lt;RevokeSaveSuccessResponse&gt;): void
 
 **示例：**
 
-FA模型示例
-
 ```js
-import distributedObject from '@ohos.data.distributedDataObject';
-import featureAbility from '@ohos.ability.featureAbility';
-// 获取context
-let context = featureAbility.getContext();
-let g_object = distributedObject.create(context, {name:"Amy", age:18, isVis:false});
-g_object.setSessionId("123456");
-// 持久化数据
-g_object.save("local", (result) => {
-    console.log("save callback");
-    console.info("save sessionId " + result.sessionId);
-    console.info("save version " + result.version);
-    console.info("save deviceId " + result.deviceId);
-});
-// 删除持久化保存的数据
-g_object.revokeSave((result) => {
-  console.log("revokeSave callback");
-  console.log("revokeSave sessionId " + result.sessionId);
-});
-```
-
-Stage模型示例
-
-```ts
-import distributedObject from '@ohos.data.distributedDataObject';
-import UIAbility from '@ohos.app.ability.UIAbility';
-// 获取context
-let context;
-class EntryAbility extends UIAbility {
-    onWindowStageCreate(windowStage) {
-        context = this.context
-    }
-}
-let g_object = distributedObject.create(context, {name:"Amy", age:18, isVis:false});
 g_object.setSessionId("123456");
 // 持久化数据
 g_object.save("local", (result) => {
-    console.log("save callback");
+    console.info("save callback");
     console.info("save sessionId " + result.sessionId);
     console.info("save version " + result.version);
     console.info("save deviceId " + result.deviceId);
 });
 // 删除持久化保存的数据
 g_object.revokeSave((result) => {
-  console.log("revokeSave callback");
-  console.log("revokeSave sessionId " + result.sessionId);
+  console.info("revokeSave callback");
+  console.info("revokeSave sessionId " + result.sessionId);
 });
 ```
 
@@ -758,18 +467,11 @@ revokeSave(): Promise&lt;RevokeSaveSuccessResponse&gt;
 
 **示例：**
 
-FA模型示例
-
 ```ts
-import distributedObject from '@ohos.data.distributedDataObject';
-import featureAbility from '@ohos.ability.featureAbility';
-// 获取context
-let context = featureAbility.getContext();
-let g_object = distributedObject.create(context, {name:"Amy", age:18, isVis:false});
 g_object.setSessionId("123456");
 // 持久化数据
 g_object.save("local").then((result) => {
-    console.log("save callback");
+    console.info("save callback");
     console.info("save sessionId " + result.sessionId);
     console.info("save version " + result.version);
     console.info("save deviceId " + result.deviceId);
@@ -778,40 +480,8 @@ g_object.save("local").then((result) => {
 });
 // 删除持久化保存的数据
 g_object.revokeSave().then((result) => {
-    console.log("revokeSave callback");
-    console.log("sessionId" + result.sessionId);
-}, () => {
-    console.error("revokeSave failed");
-});
-```
-
-Stage模型示例
-
-```ts
-import distributedObject from '@ohos.data.distributedDataObject';
-import UIAbility from '@ohos.app.ability.UIAbility';
-// 获取context
-let context;
-class EntryAbility extends UIAbility {
-    onWindowStageCreate(windowStage) {
-        context = this.context
-    }
-}
-let g_object = distributedObject.create(context, {name:"Amy", age:18, isVis:false});
-g_object.setSessionId("123456");
-g_object.save("local").then((result) => {
-    console.log("save callback");
-    console.info("save sessionId " + result.sessionId);
-    console.info("save version " + result.version);
-    console.info("save deviceId " + result.deviceId);
-}, () => {
-    console.error("save failed");
-});
-
-// 删除持久化保存的数据
-g_object.revokeSave().then((result) => {
-    console.log("revokeSave callback");
-    console.log("sessionId" + result.sessionId);
+    console.info("revokeSave callback");
+    console.info("sessionId" + result.sessionId);
 }, () => {
     console.error("revokeSave failed");
 });
@@ -852,7 +522,7 @@ let g_object = distributedObject.createDistributedObject({name:"Amy", age:18, is
 
 ## DistributedObject<sup>(deprecated)</sup>
 
-表示一个分布式数据对象。
+表示一个分布式数据对象。在使用以下接口前，需调用[createDistributedObject()](#distributedobjectcreatedistributedobjectdeprecated)获取DistributedObject对象。
 
 ### setSessionId<sup>(deprecated)</sup>
 
diff --git a/zh-cn/application-dev/reference/apis/js-apis-data-preferences.md b/zh-cn/application-dev/reference/apis/js-apis-data-preferences.md
index 332aae1d3b62f0ddf776b0c1dc6d3e8d5f902bba..d05e8e317aa6da4e471e7170a606dacf49354584 100644
--- a/zh-cn/application-dev/reference/apis/js-apis-data-preferences.md
+++ b/zh-cn/application-dev/reference/apis/js-apis-data-preferences.md
@@ -58,6 +58,7 @@ try {
 	        console.info("Failed to get preferences. code =" + err.code + ", message =" + err.message);
 	        return;
 	    }
+	    preferences = val;
 	    console.info("Succeeded in getting preferences.");
 	})
 } catch (err) {
@@ -68,26 +69,25 @@ try {
 Stage模型示例：
 
 ```ts
-// 获取context
 import UIAbility from '@ohos.app.ability.UIAbility';
-let context = null;
-class EntryAbility extends UIAbility {
-    onWindowStageCreate(windowStage){
-        context = this.context;
-    }
-}
 
 let preferences = null;
-try {
-    data_preferences.getPreferences(context, 'mystore', function (err, val) {
-	    if (err) {
-	        console.info("Failed to get preferences. code =" + err.code + ", message =" + err.message);
-	        return;
-	    }
-	    console.info("Succeeded in getting preferences.");
-	})
-} catch (err) {
-	console.info("Failed to get preferences. code =" + err.code + ", message =" + err.message);
+
+class EntryAbility extends UIAbility {
+    onWindowStageCreate(windowStage) {
+        try {
+            data_preferences.getPreferences(this.context, 'mystore', function (err, val) {
+                if (err) {
+                    console.info("Failed to get preferences. code =" + err.code + ", message =" + err.message);
+                    return;
+                }
+                preferences = val;
+                console.info("Succeeded in getting preferences.");
+            })
+        } catch (err) {
+            console.info("Failed to get preferences. code =" + err.code + ", message =" + err.message);
+        }
+    }
 }
 ```
 
@@ -128,36 +128,34 @@ try {
         preferences = object;
         console.info("Succeeded in getting preferences.");
     }).catch((err) => {
-        console.log("Failed to get preferences. code =" + err.code + ", message =" + err.message);
+        console.info("Failed to get preferences. code =" + err.code + ", message =" + err.message);
     })
 } catch(err) {
-    console.log("Failed to get preferences. code =" + err.code + ", message =" + err.message);
+    console.info("Failed to get preferences. code =" + err.code + ", message =" + err.message);
 }
 ```
 
 Stage模型示例：
 
 ```ts
-// 获取context
 import UIAbility from '@ohos.app.ability.UIAbility';
-let context = null;
-class EntryAbility extends UIAbility {
-    onWindowStageCreate(windowStage){
-        context = this.context;
-    }
-}
 
 let preferences = null;
-try {
-    let promise = data_preferences.getPreferences(context, 'mystore');
-    promise.then((object) => {
-        preferences = object;
-        console.info("Succeeded in getting preferences.");
-    }).catch((err) => {
-        console.log("Failed to get preferences. code =" + err.code + ", message =" + err.message);
-    })
-} catch(err) {
-    console.log("Failed to get preferences. code =" + err.code + ", message =" + err.message);
+
+class EntryAbility extends UIAbility {
+    onWindowStageCreate(windowStage) {
+        try {
+            let promise = data_preferences.getPreferences(this.context, 'mystore');
+            promise.then((object) => {
+                preferences = object;
+                console.info("Succeeded in getting preferences.");
+            }).catch((err) => {
+                console.info("Failed to get preferences. code =" + err.code + ", message =" + err.message);
+            })
+        } catch(err) {
+            console.info("Failed to get preferences. code =" + err.code + ", message =" + err.message);
+        }
+    }
 }
 ```
 
@@ -214,25 +212,21 @@ try {
 Stage模型示例：
 
 ```ts
-// 获取context
 import UIAbility from '@ohos.app.ability.UIAbility';
-let context = null;
 class EntryAbility extends UIAbility {
-    onWindowStageCreate(windowStage){
-        context = this.context;
-    }
-}
-
-try {
-    data_preferences.deletePreferences(context, 'mystore', function (err, val) {
-        if (err) {
+    onWindowStageCreate(windowStage) {
+        try {
+            data_preferences.deletePreferences(this.context, 'mystore', function (err, val) {
+                if (err) {
+                    console.info("Failed to delete preferences. code =" + err.code + ", message =" + err.message);
+                    return;
+                }
+                console.info("Succeeded in deleting preferences." );
+            })
+        } catch (err) {
             console.info("Failed to delete preferences. code =" + err.code + ", message =" + err.message);
-            return;
         }
-        console.info("Succeeded in deleting preferences." );
-    })
-} catch (err) {
-    console.info("Failed to delete preferences. code =" + err.code + ", message =" + err.message);
+    }
 }
 ```
 
@@ -293,25 +287,21 @@ try {
 Stage模型示例：
 
 ```ts
-// 获取context
 import UIAbility from '@ohos.app.ability.UIAbility';
-let context = null;
 class EntryAbility extends UIAbility {
-    onWindowStageCreate(windowStage){
-        context = this.context;
+    onWindowStageCreate(windowStage) {
+        try{
+            let promise = data_preferences.deletePreferences(this.context, 'mystore');
+            promise.then(() => {
+                console.info("Succeeded in deleting preferences.");
+            }).catch((err) => {
+                console.info("Failed to delete preferences. code =" + err.code + ", message =" + err.message);
+            })
+        } catch(err) {
+            console.info("Failed to delete preferences. code =" + err.code + ", message =" + err.message);
+        }
     }
 }
-
-try{
-    let promise = data_preferences.deletePreferences(context, 'mystore');
-    promise.then(() => {
-        console.info("Succeeded in deleting preferences.");
-    }).catch((err) => {
-        console.info("Failed to delete preferences. code =" + err.code + ", message =" + err.message);
-    })
-} catch(err) {
-    console.info("Failed to delete preferences. code =" + err.code + ", message =" + err.message);
-}
 ```
 
 ## data_preferences.removePreferencesFromCache
@@ -357,25 +347,21 @@ try {
 Stage模型示例：
 
 ```ts
-// 获取context
 import UIAbility from '@ohos.app.ability.UIAbility';
-let context = null;
 class EntryAbility extends UIAbility {
-    onWindowStageCreate(windowStage){
-        context = this.context;
-    }
-}
-
-try {
-    data_preferences.removePreferencesFromCache(context, 'mystore', function (err, val) {
-        if (err) {
+    onWindowStageCreate(windowStage) {
+        try {
+            data_preferences.removePreferencesFromCache(this.context, 'mystore', function (err, val) {
+                if (err) {
+                    console.info("Failed to remove preferences. code =" + err.code + ", message =" + err.message);
+                    return;
+                }
+                console.info("Succeeded in removing preferences.");
+            })
+        } catch (err) {
             console.info("Failed to remove preferences. code =" + err.code + ", message =" + err.message);
-            return;
         }
-        console.info("Succeeded in removing preferences.");
-    })
-} catch (err) {
-    console.info("Failed to remove preferences. code =" + err.code + ", message =" + err.message);
+    }
 }
 
 ```
@@ -427,25 +413,22 @@ try {
 Stage模型示例：
 
 ```ts
-// 获取context
 import UIAbility from '@ohos.app.ability.UIAbility';
-let context = null;
+
 class EntryAbility extends UIAbility {
-    onWindowStageCreate(windowStage){
-        context = this.context;
+    onWindowStageCreate(windowStage) {
+        try {
+            let promise = data_preferences.removePreferencesFromCache(this.context, 'mystore');
+            promise.then(() => {
+                console.info("Succeeded in removing preferences.");
+            }).catch((err) => {
+                console.info("Failed to remove preferences. code =" + err.code + ", message =" + err.message);
+            })
+        } catch(err) {
+            console.info("Failed to remove preferences. code =" + err.code + ", message =" + err.message);
+        }
     }
 }
-
-try {
-    let promise = data_preferences.removePreferencesFromCache(context, 'mystore');
-	promise.then(() => {
-    	console.info("Succeeded in removing preferences.");
-    }).catch((err) => {
-        console.info("Failed to remove preferences. code =" + err.code + ", message =" + err.message);
-    })
-} catch(err) {
-    console.info("Failed to remove preferences. code =" + err.code + ", message =" + err.message);
-}
 ```
 
 ## Preferences
@@ -794,10 +777,10 @@ try {
 	promise.then(() => {
         console.info("Succeeded in deleting the key 'startup'.");
     }).catch((err) => {
-        console.log("Failed to delete the key 'startup'. code =" + err.code +", message =" + err.message);
+        console.info("Failed to delete the key 'startup'. code =" + err.code +", message =" + err.message);
     })
 } catch(err) {
-    console.log("Failed to delete the key 'startup'. code =" + err.code +", message =" + err.message);
+    console.info("Failed to delete the key 'startup'. code =" + err.code +", message =" + err.message);
 }
 ```