diff --git a/zh-cn/application-dev/file-management/medialibrary-album-guidelines.md b/zh-cn/application-dev/file-management/medialibrary-album-guidelines.md
index 60043767345181ea2a247fd8b30ac155b7993d0c..0a697df0dc233a9a1500e868bde802aa7371976d 100644
--- a/zh-cn/application-dev/file-management/medialibrary-album-guidelines.md
+++ b/zh-cn/application-dev/file-management/medialibrary-album-guidelines.md
@@ -39,19 +39,19 @@ mediaLibrary提供相册相关的接口，供开发者创建、删除相册，
 
 ```ts
 async function example() {
-    let mediaType = mediaLibrary.MediaType.IMAGE;
-    let DIR_IMAGE = mediaLibrary.DirectoryType.DIR_IMAGE;
-    const context = getContext(this);
-    let media = mediaLibrary.getMediaLibrary(context);
-    const path = await media.getPublicDirectory(DIR_IMAGE);
-    //myAlbum为新建文件保存路径，也是新建相册的名称
-    media.createAsset(mediaType, 'test.jpg', path + 'myAlbum/', (err, fileAsset) => {
-        if (fileAsset === undefined) {
-            console.error('createAlbum failed, message = ' + err);
-        } else {
-            console.info('createAlbum successfully, message = ' + JSON.stringify(fileAsset));
-        }
-    });
+  let mediaType = mediaLibrary.MediaType.IMAGE;
+  let DIR_IMAGE = mediaLibrary.DirectoryType.DIR_IMAGE;
+  const context = getContext(this);
+  let media = mediaLibrary.getMediaLibrary(context);
+  const path = await media.getPublicDirectory(DIR_IMAGE);
+  //myAlbum为新建文件保存路径，也是新建相册的名称
+  media.createAsset(mediaType, 'test.jpg', path + 'myAlbum/', (err, fileAsset) => {
+    if (fileAsset === undefined) {
+      console.error('createAlbum failed, message = ' + err);
+    } else {
+      console.info('createAlbum successfully, message = ' + JSON.stringify(fileAsset));
+    }
+  });
 }
 ```
 
@@ -75,20 +75,20 @@ async function example() {
 
 ```ts
 async function example() {
-    let AlbumNoArgsfetchOp = {
-        selections: '',
-        selectionArgs: [],
-    };
-    const context = getContext(this);
-    let media = mediaLibrary.getMediaLibrary(context);
-    let albumList = await media.getAlbums(AlbumNoArgsfetchOp);
-    let album = albumList[0];
-    album.albumName = 'newAlbum';
-    //回调返回空
-    album.commitModify().then(() => {
-        console.info("albumRename successfully");
-    }).catch((err) => {
-        console.error("albumRename failed with error: " + err);
-    });
+  let AlbumNoArgsfetchOp = {
+    selections: '',
+    selectionArgs: [],
+  };
+  const context = getContext(this);
+  let media = mediaLibrary.getMediaLibrary(context);
+  let albumList = await media.getAlbums(AlbumNoArgsfetchOp);
+  let album = albumList[0];
+  album.albumName = 'newAlbum';
+  //回调返回空
+  album.commitModify().then(() => {
+    console.info("albumRename successfully");
+  }).catch((err) => {
+    console.error("albumRename failed with error: " + err);
+  });
 }
 ```
diff --git a/zh-cn/application-dev/file-management/medialibrary-filepath-guidelines.md b/zh-cn/application-dev/file-management/medialibrary-filepath-guidelines.md
index b42db693e0fe55e97061356d5040e4ff0b2cab0a..9c6475e65ea02b0e62a3eb4578c1a81921eab6d6 100644
--- a/zh-cn/application-dev/file-management/medialibrary-filepath-guidelines.md
+++ b/zh-cn/application-dev/file-management/medialibrary-filepath-guidelines.md
@@ -36,15 +36,15 @@ Openharmony上用户数据统一由媒体库进行管理，用户数据用户数
 
 ```ts
 async function example(){
-    const context = getContext(this);
-    let media = mediaLibrary.getMediaLibrary(context);
-    let DIR_CAMERA = mediaLibrary.DirectoryType.DIR_CAMERA;
-    const dicResult = await media.getPublicDirectory(DIR_CAMERA);
-    if (dicResult == 'Camera/') {
-        console.info('mediaLibraryTest : getPublicDirectory passed');
-    } else {
-        console.error('mediaLibraryTest : getPublicDirectory failed');
-    }
+  const context = getContext(this);
+  let media = mediaLibrary.getMediaLibrary(context);
+  let DIR_CAMERA = mediaLibrary.DirectoryType.DIR_CAMERA;
+  const dicResult = await media.getPublicDirectory(DIR_CAMERA);
+  if (dicResult == 'Camera/') {
+    console.info('mediaLibraryTest : getPublicDirectory passed');
+  } else {
+    console.error('mediaLibraryTest : getPublicDirectory failed');
+  }
 }
 ```
 
@@ -80,75 +80,75 @@ OpenHarmony提供应用沙箱机制，增加目录可见性数据访问防线，
 
 ```ts
 async function copyPublic2Sandbox() {
-    try {
-        const context = getContext(this);
-        let media = mediaLibrary.getMediaLibrary(context);
-        let sandboxDirPath = context.filesDir;
-        let fileKeyObj = mediaLibrary.FileKey;
-        let fileAssetFetchOp = {
-            selections: fileKeyObj.DISPLAY_NAME + '= ?',
-            selectionArgs: ['testFile.txt'],
-        };
-        let fetchResult = await media.getFileAssets(fileAssetFetchOp);
-        let fileAsset = await fetchResult.getFirstObject();
-
-        let fdPub = await fileAsset.open('rw');
-        let fdSand = await fs.open(sandboxDirPath + '/testFile.txt', fs.OpenMode.READ_WRITE | fs.OpenMode.CREATE);
-        await fs.copyFile(fdPub, fdSand.fd);
-
-        await fileAsset.close(fdPub);
-        await fs.close(fdSand.fd);
-
-        let content_sand = await fs.readText(sandboxDirPath + '/testFile.txt');
-        console.info('content read from sandbox file: ', content_sand)
-    } catch (err) {
-        console.info('[demo] copyPublic2Sandbox fail, err: ', err);
-    }
-}
-```
-
-**示例2 将应用沙箱路径文件复制到公共路径**
-
-```ts
-async function copySandbox2Public() {
+  try {
     const context = getContext(this);
     let media = mediaLibrary.getMediaLibrary(context);
     let sandboxDirPath = context.filesDir;
+    let fileKeyObj = mediaLibrary.FileKey;
+    let fileAssetFetchOp = {
+      selections: fileKeyObj.DISPLAY_NAME + '= ?',
+      selectionArgs: ['testFile.txt'],
+    };
+    let fetchResult = await media.getFileAssets(fileAssetFetchOp);
+    let fileAsset = await fetchResult.getFirstObject();
 
-    let DIR_DOCUMENTS = mediaLibrary.DirectoryType.DIR_DOCUMENTS;
-    const publicDirPath = await media.getPublicDirectory(DIR_DOCUMENTS);
-    try {
-        let fileAsset = await media.createAsset(mediaLibrary.MediaType.FILE, 'testFile02.txt', publicDirPath);
-        console.info('createFile successfully, message = ' + fileAsset);
-    } catch (err) {
-        console.error('createFile failed, message = ' + err);
-    }
-    try {
-        let fileKeyObj = mediaLibrary.FileKey;
-        let fileAssetFetchOp = {
-            selections: fileKeyObj.DISPLAY_NAME + '= ?',
-            selectionArgs: ['testFile02.txt'],
-        };
-        let fetchResult = await media.getFileAssets(fileAssetFetchOp);
-        var fileAsset = await fetchResult.getFirstObject();
-    } catch (err) {
-        console.error('file asset get failed, message = ' + err);
-    }
     let fdPub = await fileAsset.open('rw');
-    let fdSand = await fs.open(sandboxDirPath + 'testFile.txt', OpenMode.READ_WRITE);
-    await fs.copyFile(fdSand.fd, fdPub);
+    let fdSand = await fs.open(sandboxDirPath + '/testFile.txt', fs.OpenMode.READ_WRITE | fs.OpenMode.CREATE);
+    await fs.copyFile(fdPub, fdSand.fd);
+
     await fileAsset.close(fdPub);
     await fs.close(fdSand.fd);
-    let fdPubRead = await fileAsset.open('rw');
-    try {
-        let arrayBuffer = new ArrayBuffer(4096);
-        await fs.read(fdPubRead, arrayBuffer);
-        var content_pub = String.fromCharCode(...new Uint8Array(arrayBuffer));
-        fileAsset.close(fdPubRead);
-    } catch (err) {
-        console.error('read text failed, message = ', err);
-    }
-    console.info('content read from public file: ', content_pub);
+
+    let content_sand = await fs.readText(sandboxDirPath + '/testFile.txt');
+    console.info('content read from sandbox file: ', content_sand)
+  } catch (err) {
+    console.info('[demo] copyPublic2Sandbox fail, err: ', err);
+  }
+}
+```
+
+**示例2 将应用沙箱路径文件复制到公共路径**
+
+```ts
+async function copySandbox2Public() {
+  const context = getContext(this);
+  let media = mediaLibrary.getMediaLibrary(context);
+  let sandboxDirPath = context.filesDir;
+
+  let DIR_DOCUMENTS = mediaLibrary.DirectoryType.DIR_DOCUMENTS;
+  const publicDirPath = await media.getPublicDirectory(DIR_DOCUMENTS);
+  try {
+    let fileAsset = await media.createAsset(mediaLibrary.MediaType.FILE, 'testFile02.txt', publicDirPath);
+    console.info('createFile successfully, message = ' + fileAsset);
+  } catch (err) {
+    console.error('createFile failed, message = ' + err);
+  }
+  try {
+    let fileKeyObj = mediaLibrary.FileKey;
+    let fileAssetFetchOp = {
+      selections: fileKeyObj.DISPLAY_NAME + '= ?',
+      selectionArgs: ['testFile02.txt'],
+    };
+    let fetchResult = await media.getFileAssets(fileAssetFetchOp);
+    var fileAsset = await fetchResult.getFirstObject();
+  } catch (err) {
+    console.error('file asset get failed, message = ' + err);
+  }
+  let fdPub = await fileAsset.open('rw');
+  let fdSand = await fs.open(sandboxDirPath + 'testFile.txt', OpenMode.READ_WRITE);
+  await fs.copyFile(fdSand.fd, fdPub);
+  await fileAsset.close(fdPub);
+  await fs.close(fdSand.fd);
+  let fdPubRead = await fileAsset.open('rw');
+  try {
+    let arrayBuffer = new ArrayBuffer(4096);
+    await fs.read(fdPubRead, arrayBuffer);
+    var content_pub = String.fromCharCode(...new Uint8Array(arrayBuffer));
+    fileAsset.close(fdPubRead);
+  } catch (err) {
+    console.error('read text failed, message = ', err);
+  }
+  console.info('content read from public file: ', content_pub);
 }
 ```
 
@@ -166,20 +166,20 @@ async function copySandbox2Public() {
 
 1. 创建用于读写示例的文件。
 
-   ```ts
-   async function example() {
-       let mediaType = mediaLibrary.MediaType.FILE;
-       let DIR_DOCUMENTS = mediaLibrary.DirectoryType.DIR_DOCUMENTS;
-       const context = getContext(this);
-       let media = mediaLibrary.getMediaLibrary(context);
-       const path = await media.getPublicDirectory(DIR_DOCUMENTS);
-       media.createAsset(mediaType, "testFile.text", path).then((asset) => {
-           console.info("createAsset successfully:" + JSON.stringify(asset));
-       }).catch((err) => {
-           console.error("createAsset failed with error: " + err);
-       });
-   }
-   ```
+```ts
+async function example() {
+  let mediaType = mediaLibrary.MediaType.FILE;
+  let DIR_DOCUMENTS = mediaLibrary.DirectoryType.DIR_DOCUMENTS;
+  const context = getContext(this);
+  let media = mediaLibrary.getMediaLibrary(context);
+  const path = await media.getPublicDirectory(DIR_DOCUMENTS);
+  media.createAsset(mediaType, "testFile.text", path).then((asset) => {
+    console.info("createAsset successfully:" + JSON.stringify(asset));
+  }).catch((err) => {
+    console.error("createAsset failed with error: " + err);
+  });
+}
+```
 
 2. 使用open打开文件。
 
@@ -195,25 +195,25 @@ async function copySandbox2Public() {
 
 ```ts
 async function writeOnlyPromise() {
-    const context = getContext(this);
-    let media = mediaLibrary.getMediaLibrary(context);
-    let fileKeyObj = mediaLibrary.FileKey;
-    let fileAssetFetchOp = {
-        selections: fileKeyObj.DISPLAY_NAME + '= ?',
-        selectionArgs: ['testFile.txt'],
-    };
-    let fetchResult = await media.getFileAssets(fileAssetFetchOp);
-    let fileAsset = await fetchResult.getFirstObject();
-    console.info('fileAssetName: ', fileAsset.displayName);
-
-    try {
-        let fd = await fileAsset.open('w');
-        console.info('file descriptor: ', fd);
-        await fs.write(fd, "Write file test content.");
-        await fileAsset.close(fd);
-    } catch (err) {
-        console.error('write file failed, message = ', err);
-    }
+  const context = getContext(this);
+  let media = mediaLibrary.getMediaLibrary(context);
+  let fileKeyObj = mediaLibrary.FileKey;
+  let fileAssetFetchOp = {
+    selections: fileKeyObj.DISPLAY_NAME + '= ?',
+    selectionArgs: ['testFile.txt'],
+  };
+  let fetchResult = await media.getFileAssets(fileAssetFetchOp);
+  let fileAsset = await fetchResult.getFirstObject();
+  console.info('fileAssetName: ', fileAsset.displayName);
+
+  try {
+    let fd = await fileAsset.open('w');
+    console.info('file descriptor: ', fd);
+    await fs.write(fd, "Write file test content.");
+    await fileAsset.close(fd);
+  } catch (err) {
+    console.error('write file failed, message = ', err);
+  }
 }
 ```
 
@@ -221,29 +221,29 @@ async function writeOnlyPromise() {
 
 ```ts
 async function readOnlyPromise() {
-    const context = getContext(this);
-    let media = mediaLibrary.getMediaLibrary(context);
-    let fileKeyObj = mediaLibrary.FileKey;
-    let fileAssetFetchOp = {
-        selections: fileKeyObj.DISPLAY_NAME + '= ?' ,
-        selectionArgs: ['testFile.txt'],
-    };
-    let fetchResult = await media.getFileAssets(fileAssetFetchOp);
-    let fileAsset = await fetchResult.getFirstObject();
-    console.info('fileAssetName: ', fileAsset.displayName);
-
-    try {
-        let fd = await fileAsset.open('r');
-        let arrayBuffer = new ArrayBuffer(4096);
-        await fs.read(fd, arrayBuffer);
-        let fileContent = String.fromCharCode(...new Uint8Array(arrayBuffer));
-        globalThis.fileContent = fileContent;
-        globalThis.fileName = fileAsset.displayName;
-        console.info('file content: ', fileContent);
-        await fileAsset.close(fd);
-    } catch (err) {
-        console.error('read file failed, message = ', err);
-    }
+  const context = getContext(this);
+  let media = mediaLibrary.getMediaLibrary(context);
+  let fileKeyObj = mediaLibrary.FileKey;
+  let fileAssetFetchOp = {
+    selections: fileKeyObj.DISPLAY_NAME + '= ?' ,
+    selectionArgs: ['testFile.txt'],
+  };
+  let fetchResult = await media.getFileAssets(fileAssetFetchOp);
+  let fileAsset = await fetchResult.getFirstObject();
+  console.info('fileAssetName: ', fileAsset.displayName);
+
+  try {
+    let fd = await fileAsset.open('r');
+    let arrayBuffer = new ArrayBuffer(4096);
+    await fs.read(fd, arrayBuffer);
+    let fileContent = String.fromCharCode(...new Uint8Array(arrayBuffer));
+    globalThis.fileContent = fileContent;
+    globalThis.fileName = fileAsset.displayName;
+    console.info('file content: ', fileContent);
+    await fileAsset.close(fd);
+  } catch (err) {
+    console.error('read file failed, message = ', err);
+  }
 }
 ```
 
diff --git a/zh-cn/application-dev/file-management/medialibrary-overview.md b/zh-cn/application-dev/file-management/medialibrary-overview.md
index 64dd3e91f9a1c955d8c1786d1378c8f6c5527281..5ccc5310d3304afab08d7ac98858b32a93e9bb49 100644
--- a/zh-cn/application-dev/file-management/medialibrary-overview.md
+++ b/zh-cn/application-dev/file-management/medialibrary-overview.md
@@ -63,65 +63,65 @@ let media = mediaLibrary.getMediaLibrary(context);
 
 1. 在配置文件module.json5中声明权限。在配置文件的“module”标签内，增加“requestPermissions”标签，标签内容请根据实际情况填写。标签说明可参考[访问控制（权限）开发指导](../security/accesstoken-guidelines.md)。
 
-   ```json
-   {
-       "module": {
-           "requestPermissions": [
-               {
-                   "name": "ohos.permission.MEDIA_LOCATION",
-                   "reason": "$string:reason",
-                   "usedScene": {
-                       "abilities": [
-                         "MainAbility"
-                       ],
-                       "when": "always"
-               }
-               },
-               {
-                   "name": "ohos.permission.READ_MEDIA",
-                   "reason": "$string:reason",
-                   "usedScene": {
-                       "abilities": [
-                           "MainAbility"
-                       ],
-                       "when": "always"
-                   }
-               },
-               {
-                   "name": "ohos.permission.WRITE_MEDIA",
-                   "reason": "$string:reason",
-                   "usedScene": {
-                       "abilities": [
-                           "MainAbility"
-                       ],
-                       "when": "always"
-                   }
-               }
-           ]
-       }
-   }    
-   ```
+```json
+{
+  "module": {
+    "requestPermissions": [
+      {
+        "name": "ohos.permission.MEDIA_LOCATION",
+        "reason": "$string:reason",
+        "usedScene": {
+          "abilities": [
+            "EntryAbility"
+          ],
+          "when": "always"
+        }
+      },
+      {
+        "name": "ohos.permission.READ_MEDIA",
+        "reason": "$string:reason",
+        "usedScene": {
+          "abilities": [
+            "EntryAbility"
+          ],
+          "when": "always"
+        }
+      },
+      {
+        "name": "ohos.permission.WRITE_MEDIA",
+        "reason": "$string:reason",
+        "usedScene": {
+          "abilities": [
+            "EntryAbility"
+          ],
+          "when": "always"
+        }
+      }
+    ]
+  }
+}    
+```
 
 2. 在Ability.ts中onWindowStageCreate里调用requestPermissionsFromUser进行权限校验，可以选择需要动态申请获取的权限自行添加相应代码
 
-   ```ts
-   import UIAbility from '@ohos.app.ability.UIAbility';
-   import abilityAccessCtrl, {Permissions} from '@ohos.abilityAccessCtrl';
-   
-   export default class EntryAbility extends UIAbility {
-        onWindowStageCreate(windowStage) {
-            let list : Array<Permissions> = ['ohos.permission.READ_MEDIA', 'ohos.permission.WRITE_MEDIA'];
-            let permissionRequestResult;
-            let atManager = abilityAccessCtrl.createAtManager();
-            atManager.requestPermissionsFromUser(this.context, list, (err, result) => {
-                if (err) {
-                    console.error('requestPermissionsFromUserError: ' + JSON.stringify(err));
-                } else {
-                    permissionRequestResult=result;
-                    console.info('permissionRequestResult: ' + JSON.stringify(permissionRequestResult));
-                }    
-            });       
-        }
-    }
-   ```
+```ts
+import UIAbility from '@ohos.app.ability.UIAbility';
+import abilityAccessCtrl, {Permissions} from '@ohos.abilityAccessCtrl';
+
+export default class EntryAbility extends UIAbility {
+  onWindowStageCreate(windowStage) {
+    let list : Array<Permissions> = ['ohos.permission.READ_MEDIA', 'ohos.permission.WRITE_MEDIA'];
+    let permissionRequestResult;
+    let atManager = abilityAccessCtrl.createAtManager();
+    atManager.requestPermissionsFromUser(this.context, list, (err, result) => {
+      if (err) {
+        console.error('requestPermissionsFromUserError: ' + JSON.stringify(err));
+      } else {
+        permissionRequestResult = result;
+        console.info('permissionRequestResult: ' + JSON.stringify(permissionRequestResult));
+      }
+    });       
+  }
+}
+```
 
diff --git a/zh-cn/application-dev/file-management/medialibrary-resource-guidelines.md b/zh-cn/application-dev/file-management/medialibrary-resource-guidelines.md
index 9277bfdf74bbd442f475e409b47325ba785f4a79..f7ff385787524cb3209c2cc3b54bc427f84ca8b2 100644
--- a/zh-cn/application-dev/file-management/medialibrary-resource-guidelines.md
+++ b/zh-cn/application-dev/file-management/medialibrary-resource-guidelines.md
@@ -33,27 +33,27 @@ selectionArgs： MediaType.IMAGE，媒体类型为图片。
 
 ```ts
 async function example() {
-    let fileKeyObj = mediaLibrary.FileKey;
-    let fileType = mediaLibrary.MediaType.IMAGE;
-    let option = {
-        selections: fileKeyObj.MEDIA_TYPE + '= ?',
-        selectionArgs: [fileType.toString()],
-    };
-    const context = getContext(this);
-    let media = mediaLibrary.getMediaLibrary(context);
-    const fetchFileResult = await media.getFileAssets(option);
-    fetchFileResult.getFirstObject().then((fileAsset) => {
-        console.log('getFirstObject.displayName : ' + fileAsset.displayName);
-        for (let i = 1; i < fetchFileResult.getCount(); i++) {
-            fetchFileResult.getNextObject().then((fileAsset) => {
-                console.info('fileAsset.displayName ' + i + ': ' + fileAsset.displayName);
-            }).catch((err) => {
-                console.error('Failed to get next object: ' + err);
-            });
-        }
-    }).catch((err) => {
-        console.error('Failed to get first object: ' + err);
-    });
+  let fileKeyObj = mediaLibrary.FileKey;
+  let fileType = mediaLibrary.MediaType.IMAGE;
+  let option = {
+    selections: fileKeyObj.MEDIA_TYPE + '= ?',
+    selectionArgs: [fileType.toString()],
+  };
+  const context = getContext(this);
+  let media = mediaLibrary.getMediaLibrary(context);
+  const fetchFileResult = await media.getFileAssets(option);
+  fetchFileResult.getFirstObject().then((fileAsset) => {
+    console.log('getFirstObject.displayName : ' + fileAsset.displayName);
+    for (let i = 1; i < fetchFileResult.getCount(); i++) {
+      fetchFileResult.getNextObject().then((fileAsset) => {
+        console.info('fileAsset.displayName ' + i + ': ' + fileAsset.displayName);
+      }).catch((err) => {
+        console.error('Failed to get next object: ' + err);
+      });
+    }
+  }).catch((err) => {
+    console.error('Failed to get first object: ' + err);
+  });
 }
 ```
 
@@ -67,26 +67,26 @@ selectionArgs：2022-8-5，具体添加时间的字符串。
 
 ```ts
 async function example() {
-    let fileKeyObj = mediaLibrary.FileKey;
-    let option = {
+  let fileKeyObj = mediaLibrary.FileKey;
+  let option = {
     selections: fileKeyObj.DATE_ADDED + '> ?',
     selectionArgs: ['2022-8-5'],
-    };
-    const context = getContext(this);
-    let media = mediaLibrary.getMediaLibrary(context);
-    const fetchFileResult = await media.getFileAssets(option);
-    fetchFileResult.getFirstObject().then((fileAsset) => {
-        console.info('getFirstObject.displayName : ' + fileAsset.displayName);
-        for (let i = 1; i < fetchFileResult.getCount(); i++) {
-            fetchFileResult.getNextObject().then((fileAsset) => {
-                console.info('fileAsset.displayName ' + i + ': ' + fileAsset.displayName);
-            }).catch((err) => {
-                console.error('Failed to get next object: ' + err);
-            });
-        }
-    }).catch((err) => {
-        console.error('Failed to get first object: ' + err);
-    });
+  };
+  const context = getContext(this);
+  let media = mediaLibrary.getMediaLibrary(context);
+  const fetchFileResult = await media.getFileAssets(option);
+  fetchFileResult.getFirstObject().then((fileAsset) => {
+    console.info('getFirstObject.displayName : ' + fileAsset.displayName);
+    for (let i = 1; i < fetchFileResult.getCount(); i++) {
+      fetchFileResult.getNextObject().then((fileAsset) => {
+        console.info('fileAsset.displayName ' + i + ': ' + fileAsset.displayName);
+      }).catch((err) => {
+        console.error('Failed to get next object: ' + err);
+      });
+    }
+  }).catch((err) => {
+    console.error('Failed to get first object: ' + err);
+  });
 }
 ```
 
@@ -98,28 +98,28 @@ order： FileKey.DATE_ADDED，根据文件添加日期排序；并设置排列
 
 ```ts
 async function example() {
-    let fileKeyObj = mediaLibrary.FileKey;
-    let fileType = mediaLibrary.MediaType.IMAGE;
-    let option = {
-        selections: fileKeyObj.MEDIA_TYPE + '= ?',
-        selectionArgs: [fileType.toString()],
-        order: fileKeyObj.DATE_ADDED + " DESC",
-    };
-    const context = getContext(this);
-    let media = mediaLibrary.getMediaLibrary(context);
-    const fetchFileResult = await media.getFileAssets(option);
-    fetchFileResult.getFirstObject().then((fileAsset) => {
-        console.info('getFirstObject.displayName : ' + fileAsset.displayName);
-        for (let i = 1; i < fetchFileResult.getCount(); i++) {
-            fetchFileResult.getNextObject().then((fileAsset) => {
-                console.info('fileAsset.displayName ' + i + ': ' + fileAsset.displayName);
-            }).catch((err) => {
-                console.error('Failed to get next object: ' + err);
-            });
-        }
-    }).catch((err) => {
-        console.error('Failed to get first object: ' + err);
-    });
+  let fileKeyObj = mediaLibrary.FileKey;
+  let fileType = mediaLibrary.MediaType.IMAGE;
+  let option = {
+    selections: fileKeyObj.MEDIA_TYPE + '= ?',
+    selectionArgs: [fileType.toString()],
+    order: fileKeyObj.DATE_ADDED + " DESC",
+  };
+  const context = getContext(this);
+  let media = mediaLibrary.getMediaLibrary(context);
+  const fetchFileResult = await media.getFileAssets(option);
+  fetchFileResult.getFirstObject().then((fileAsset) => {
+    console.info('getFirstObject.displayName : ' + fileAsset.displayName);
+    for (let i = 1; i < fetchFileResult.getCount(); i++) {
+      fetchFileResult.getNextObject().then((fileAsset) => {
+        console.info('fileAsset.displayName ' + i + ': ' + fileAsset.displayName);
+      }).catch((err) => {
+        console.error('Failed to get next object: ' + err);
+      });
+    }
+  }).catch((err) => {
+    console.error('Failed to get first object: ' + err);
+  });
 }
 ```
 
@@ -133,24 +133,23 @@ selectionArgs：'myAlbum'，具体相册名称。
 
 ```ts
 async function example() {
-    let fileKeyObj = mediaLibrary.FileKey;
-    let fileType = mediaLibrary.MediaType.IMAGE;
-    let option = {
-        selections: fileKeyObj.ALBUM_NAME + '= ?',
-        selectionArgs: ['myAlbum'],
-    };
-    const context = getContext(this);
-    let media = mediaLibrary.getMediaLibrary(context);
-    const fetchFileResult = await media.getFileAssets(option);
-    if (albumList.length > 0) {
-        fetchFileResult.getFirstObject().then((album) => {
-            console.info('getFirstObject.displayName : ' + album.albumName);
-        }).catch((err) => {
-            console.error('Failed to get first object: ' + err);
-        });
-    } else {
-        console.info('getAlbum list is: 0');
-    }
+  let fileKeyObj = mediaLibrary.FileKey;
+  let option = {
+    selections: fileKeyObj.ALBUM_NAME + '= ?',
+    selectionArgs: ['myAlbum'],
+  };
+  const context = getContext(this);
+  let media = mediaLibrary.getMediaLibrary(context);
+  const fetchFileResult = await media.getFileAssets(option);
+  if (albumList.length > 0) {
+    fetchFileResult.getFirstObject().then((album) => {
+      console.info('getFirstObject.displayName : ' + album.albumName);
+    }).catch((err) => {
+      console.error('Failed to get first object: ' + err);
+    });
+  } else {
+    console.info('getAlbum list is: 0');
+  }
 }
 ```
 
@@ -169,24 +168,24 @@ async function example() {
 
 1. 建立检索条件，用于获取目的相册实例。
 
-   ```ts
-   let fileKeyObj = mediaLibrary.FileKey;
-   let AlbumNoArgsFetchOp = {
-       selections: fileKeyObj.ALBUM_NAME + '= ?',
-       selectionArgs: ['新建相册1']
-   }
-   ```
+```ts
+let fileKeyObj = mediaLibrary.FileKey;
+let AlbumNoArgsFetchOp = {
+  selections: fileKeyObj.ALBUM_NAME + '= ?',
+  selectionArgs: ['新建相册1']
+}
+```
 
 2. 建立检索条件，用于获取目的相册下的视频资源。
 
-   ```ts
-   let fileKeyObj = mediaLibrary.FileKey;
-   let videoType = mediaLibrary.MediaType.VIDEO;
-   let videoFetchOp  = {
-       selections: fileKeyObj.MEDIA_TYPE + '= ?',
-       selectionArgs: [videoType.toString()],
-   }
-   ```
+```ts
+let fileKeyObj = mediaLibrary.FileKey;
+let videoType = mediaLibrary.MediaType.VIDEO;
+let videoFetchOp  = {
+  selections: fileKeyObj.MEDIA_TYPE + '= ?',
+  selectionArgs: [videoType.toString()],
+}
+```
 
 3. 通过Album.getFileAssets获取对应的资源。
 
@@ -194,28 +193,28 @@ async function example() {
 
 ```ts
 async function getCameraImagePromise() {
-    const context = getContext(this);
-    let media = mediaLibrary.getMediaLibrary(context);
-    let fileKeyObj = mediaLibrary.FileKey;
-    let videoType = mediaLibrary.MediaType.VIDEO;
-    let videoFetchOp = {
-        selections: fileKeyObj.MEDIA_TYPE + '= ?',
-        selectionArgs: [videoType.toString()],
-    }
-    let AlbumNoArgsFetchOp = {
-        selections: fileKeyObj.ALBUM_NAME + '= ?',
-        selectionArgs: ['新建相册1']
-    }
-
-    let albumList = await media.getAlbums(AlbumNoArgsFetchOp);
-    if (albumList.length > 0) {
-        const album = albumList[0];
-        let fetchFileResult = await album.getFileAssets(videoFetchOp);
-        let count = fetchFileResult.getCount();
-        console.info("get mediaLibrary VIDEO number", count);
-    } else {
-        console.info('getAlbum list is: 0');
-    }
+  const context = getContext(this);
+  let media = mediaLibrary.getMediaLibrary(context);
+  let fileKeyObj = mediaLibrary.FileKey;
+  let videoType = mediaLibrary.MediaType.VIDEO;
+  let videoFetchOp = {
+    selections: fileKeyObj.MEDIA_TYPE + '= ?',
+    selectionArgs: [videoType.toString()],
+  }
+  let AlbumNoArgsFetchOp = {
+    selections: fileKeyObj.ALBUM_NAME + '= ?',
+    selectionArgs: ['新建相册1']
+  }
+
+  let albumList = await media.getAlbums(AlbumNoArgsFetchOp);
+  if (albumList.length > 0) {
+    const album = albumList[0];
+    let fetchFileResult = await album.getFileAssets(videoFetchOp);
+    let count = fetchFileResult.getCount();
+    console.info("get mediaLibrary VIDEO number", count);
+  } else {
+    console.info('getAlbum list is: 0');
+  }
 }
 ```
 
@@ -243,32 +242,32 @@ async function getCameraImagePromise() {
 
 ```ts
 async function getFirstThumbnailPromise() {
-    const context = getContext(this);
-    let media = mediaLibrary.getMediaLibrary(context);
-    let fileKeyObj = mediaLibrary.FileKey;
-    let imageType = mediaLibrary.MediaType.IMAGE;
-    let imagesFetchOp = {
-        selections: fileKeyObj.MEDIA_TYPE + '= ?',
-        selectionArgs: [imageType.toString()],
-    }
-
-    let size = { width: 720, height: 720 };
-    const fetchFileResult = await media.getFileAssets(imagesFetchOp);
-    if (fetchFileResult === undefined) {
-        console.error("get image failed with error");
-        return;
-    } else {
-        const asset = await fetchFileResult.getFirstObject();
-        asset.getThumbnail(size).then((pixelMap) => {
-            pixelMap.getImageInfo().then((info) => {
-              console.info('get Thumbnail info: ' + "width: " + info.size.width + " height: " + info.size.height);
-            }).catch((err) => {
-              console.error("getImageInfo failed with error: " + err);
-            });
-        }).catch((err) => {
-            console.error("getImageInfo failed with error: " + err);
-        });
-    }
+  const context = getContext(this);
+  let media = mediaLibrary.getMediaLibrary(context);
+  let fileKeyObj = mediaLibrary.FileKey;
+  let imageType = mediaLibrary.MediaType.IMAGE;
+  let imagesFetchOp = {
+    selections: fileKeyObj.MEDIA_TYPE + '= ?',
+    selectionArgs: [imageType.toString()],
+  }
+
+  let size = { width: 720, height: 720 };
+  const fetchFileResult = await media.getFileAssets(imagesFetchOp);
+  if (fetchFileResult === undefined) {
+    console.error("get image failed with error");
+    return;
+  } else {
+    const asset = await fetchFileResult.getFirstObject();
+    asset.getThumbnail(size).then((pixelMap) => {
+      pixelMap.getImageInfo().then((info) => {
+        console.info('get Thumbnail info: ' + "width: " + info.size.width + " height: " + info.size.height);
+      }).catch((err) => {
+        console.error("getImageInfo failed with error: " + err);
+      });
+    }).catch((err) => {
+      console.error("getImageInfo failed with error: " + err);
+    });
+  }
 }
 ```
 
@@ -286,16 +285,16 @@ async function getFirstThumbnailPromise() {
 
 ```ts
 async function example() {
-    let mediaType = mediaLibrary.MediaType.FILE;
-    let DIR_DOCUMENTS = mediaLibrary.DirectoryType.DIR_DOCUMENTS;
-    const context = getContext(this);
-    let media = mediaLibrary.getMediaLibrary(context);
-    const path = await media.getPublicDirectory(DIR_DOCUMENTS);
-    media.createAsset(mediaType, "testFile.text", path).then((asset) => {
-        console.info("createAsset successfully:"+ JSON.stringify(asset));
-    }).catch((err) => {
-        console.error("createAsset failed with error: " + err);
-    });
+  let mediaType = mediaLibrary.MediaType.FILE;
+  let DIR_DOCUMENTS = mediaLibrary.DirectoryType.DIR_DOCUMENTS;
+  const context = getContext(this);
+  let media = mediaLibrary.getMediaLibrary(context);
+  const path = await media.getPublicDirectory(DIR_DOCUMENTS);
+  media.createAsset(mediaType, "testFile.text", path).then((asset) => {
+    console.info("createAsset successfully:"+ JSON.stringify(asset));
+  }).catch((err) => {
+    console.error("createAsset failed with error: " + err);
+  });
 }
 ```
 
@@ -321,26 +320,26 @@ async function example() {
 
 ```ts
 async function example() {
-    let fileKeyObj = mediaLibrary.FileKey;
-    let fileType = mediaLibrary.MediaType.FILE;
-    let option = {
-        selections: fileKeyObj.MEDIA_TYPE + '= ?',
-        selectionArgs: [fileType.toString()],
-    };
-    const context = getContext(this);
-    let media = mediaLibrary.getMediaLibrary(context);
-    const fetchFileResult = await media.getFileAssets(option);
-    let asset = await fetchFileResult.getFirstObject();
-    if (asset === undefined) {
-        console.error('asset not exist');
-        return;
-    }
-    //回调为空
-    asset.trash(true).then(() => {
-        console.info("trash successfully");
-    }).catch((err) => {
-        console.error("trash failed with error: " + err);
-    });
+  let fileKeyObj = mediaLibrary.FileKey;
+  let fileType = mediaLibrary.MediaType.FILE;
+  let option = {
+    selections: fileKeyObj.MEDIA_TYPE + '= ?',
+    selectionArgs: [fileType.toString()],
+  };
+  const context = getContext(this);
+  let media = mediaLibrary.getMediaLibrary(context);
+  const fetchFileResult = await media.getFileAssets(option);
+  let asset = await fetchFileResult.getFirstObject();
+  if (asset === undefined) {
+    console.error('asset not exist');
+    return;
+  }
+  //回调为空
+  asset.trash(true).then(() => {
+    console.info("trash successfully");
+  }).catch((err) => {
+    console.error("trash failed with error: " + err);
+  });
 }
 ```
 
@@ -369,28 +368,28 @@ async function example() {
 
 ```ts
 async function example() {
-    let fileKeyObj = mediaLibrary.FileKey;
-    let fileType = mediaLibrary.MediaType.IMAGE;
-    let option = {
-        selections: fileKeyObj.MEDIA_TYPE + '= ?',
-        selectionArgs: [fileType.toString()],
-    };
-    const context = getContext(this);
-    let media = mediaLibrary.getMediaLibrary(context);
-    const fetchFileResult = await media.getFileAssets(option);
-    let asset = await fetchFileResult.getFirstObject();
-    if (asset === undefined) {
-        console.error('asset not exist');
-        return;
+  let fileKeyObj = mediaLibrary.FileKey;
+  let fileType = mediaLibrary.MediaType.IMAGE;
+  let option = {
+    selections: fileKeyObj.MEDIA_TYPE + '= ?',
+    selectionArgs: [fileType.toString()],
+  };
+  const context = getContext(this);
+  let media = mediaLibrary.getMediaLibrary(context);
+  const fetchFileResult = await media.getFileAssets(option);
+  let asset = await fetchFileResult.getFirstObject();
+  if (asset === undefined) {
+    console.error('asset not exist');
+    return;
+  }
+  asset.displayName = 'newImage.jpg';
+  //回调为空
+  asset.commitModify((err) => {
+    if (err) {
+      console.error('fileRename Failed ');
+      return;
     }
-    asset.displayName = 'newImage.jpg';
-    //回调为空
-    asset.commitModify((err) => {
-        if (err) {
-            console.error('fileRename Failed ');
-            return;
-        }
-        console.info('fileRename successful.');
-    });
+    console.info('fileRename successful.');
+  });
 }
 ```