update docs

Signed-off-by: NAnnie_wang <annie.wangli@huawei.com>

en/release-notes/changelogs/OpenHarmony_4.0.8.2/changelogs-mediaLibrary.md

@@ -21,18 +21,20 @@ For applications developed based on earlier versions, pay attention to the itera
 | medialibrary   |  **function** getAlbums(options: MediaFetchOptions): Promise<Array<Album>> | Interface compatibility changed    |
 | medialibrary   |  **function** FileAsset.commitModify(callback: AsyncCallback<void>): void | Interface compatibility changed    |
 | medialibrary   |  **function** FileAsset.commitModify(): Promise<void> | Interface compatibility changed    |
+| medialibrary   |  **function** FileAsset.deleteAsset(uri: string, callback: AsyncCallback<void>): void | Interface compatibility changed    |
+| medialibrary   |  **function** FileAsset.deleteAsset(uri: string): Promise<void> | Interface compatibility changed    |
 
 **Adaptation Guide**
 
 **getFileAssets**
 
-From API version 10, the albums represented by physical directories are replaced by logical albums, which allows multiple files in an album and presence of a file in multiple albums. This design, however, makes **parent**, **albumId**, **albumUri**, and **albumName** incompatible. They cannot be used as parameters of **MediaFetchOptions** in **getFileAssets()**. See the following example:
+From API version 10, the albums represented by physical directories are replaced by logical albums, which allow multiple files in an album and presence of a file in multiple albums. This design, however, makes **parent**, **albumId**, **albumUri**, and **albumName** incompatible. They cannot be used as parameters of **MediaFetchOptions** in **getFileAssets()**. The following is an example of incorrect use of the APIs.
 
-1. Use [getMediaLibrary](../../../application-dev/reference/apis/js-apis-medialibrary.md#medialibrarygetmedialibrary) to obtain a **MediaLibrary** instance.
-2. Use [MediaFetchOptions](../../../application-dev/reference/apis/js-apis-medialibrary.md#mediafetchoptions7) to create the file fetching options.
-3. Use [getFileAssets](../../../application-dev/reference/apis/js-apis-medialibrary.md#getfileassets7) to obtain file assets.
+1. Call [getMediaLibrary](../../../application-dev/reference/apis/js-apis-medialibrary.md#medialibrarygetmedialibrary) to obtain a **MediaLibrary** instance.
+2. Call [MediaFetchOptions](../../../application-dev/reference/apis/js-apis-medialibrary.md#mediafetchoptions7) to create the file fetching options.
+3. Call [getFileAssets](../../../application-dev/reference/apis/js-apis-medialibrary.md#getfileassets7) to obtain file assets.
 
-**Incorrect code example**:
+**Example (incorrect)**:
 
 ```js
 import mediaLibrary from '@ohos.multimedia.mediaLibrary';
@@ -58,7 +60,7 @@ async function example() {
 
 Use **getFileAssets()** as follows:
 
-**Correct code example**:
+**Example (correct)**:
 
 ```js
 import mediaLibrary from '@ohos.multimedia.mediaLibrary';
@@ -84,17 +86,17 @@ async function example() {
 
 **createAsset**
 
-From the SDK of API version 10, **relativePath** is no longer associated with an album. After a file is created, the last-level directory of **relativePath** is not displayed as an album.
+Since the SDK of API version 10, **relativePath** is no longer associated with an album. After a file is created, the last-level directory of **relativePath** is not displayed as an album.
 
 **getAlbums**
 
-From the SDK of API version 10, **relativePath** is no longer associated with an album. Therefore, **relativePath** cannot be used as a search criterion in **getAlbums**, and the values of **ALBUM_NAME** can be **Camera** and **Screenshots** only. See the following example:
+Since the SDK of API version 10, **relativePath** is no longer associated with an album. Therefore, **relativePath** cannot be used as a search criterion in **getAlbums**, and the values of **ALBUM_NAME** can be **Camera** and **Screenshots** only. The following is an example of incorrect use of the APIs.
 
 1. Use [getMediaLibrary](../../../application-dev/reference/apis/js-apis-medialibrary.md#medialibrarygetmedialibrary) to obtain a **MediaLibrary** instance.
 2. Use [MediaFetchOptions](../../../application-dev/reference/apis/js-apis-medialibrary.md#mediafetchoptions7) to create the album fetching options.
 3. Use [getAlbums](../../../application-dev/reference/apis/js-apis-medialibrary.md#getalbums7) to obtain albums.
 
-**Incorrect code example**:
+**Example (incorrect)**:
 
 ```js
 import mediaLibrary from '@ohos.multimedia.mediaLibrary';
@@ -119,7 +121,7 @@ async function example() {
 
 The following example shows how to obtain **Camera** and **Screenshots** albums:
 
-**Correct code example**:
+**Example (correct)**:
 
 ```js
 import mediaLibrary from '@ohos.multimedia.mediaLibrary';
@@ -145,3 +147,40 @@ async function example() {
 **FileAsset.commitModify**
 
 The **orientation** attribute for audio is deleted from the SDK of API version 10. When **commitModify** is used, the **orientation** attribute of audio resources cannot be modified.
+
+**FileAsset.deleteAsset**
+
+The change has resolved a known issue of the file deletion mechanism. This issue may cause a system application to permanently delete a file that is not in the trash using **MediaLibrary.deleteAsset**.
+
+The correct procedure for a system application to permanently delete a file is as follows:
+
+1. Call [getFileAssets](../../../application-dev/reference/apis/js-apis-medialibrary.md#getfileassets7) to obtain file assets.
+2. Call [FileAsset.trash](../../../application-dev/reference/apis/js-apis-medialibrary.md#trash8) to move the file to the trash.
+3. Call [MediaLibrary.deleteAsset](../../../application-dev/reference/apis/js-apis-medialibrary.md#deleteasset8) to permanently delete the file.
+
+**Example (correct)**:
+
+```js
+import mediaLibrary from '@ohos.multimedia.mediaLibrary';
+
+async function example() {
+  try {
+    let context = getContext(this);
+    let media = mediaLibrary.getMediaLibrary(context);
+    let fileKeyObj = mediaLibrary.FileKey;
+    let imageType = mediaLibrary.MediaType.IMAGE;
+    let getImageOp = {
+      selections: fileKeyObj.MEDIA_TYPE + '= ?',
+      selectionArgs: [imageType.toString()],
+    };
+    const fetchFileResult = await media.getFileAssets(getImageOp); 
+    const fileAsset = await fetchFileResult.getFirstObject();
+    // Delete the file (move it to the trash of Gallery).
+    await fileAsset.trash(true);
+    // Delete the file from the system permanently.
+    await media.deleteAsset(fileAsset.uri);
+  } catch (err) {
+    console.error('Failed to delete asset permanently from system, error: ' + err);
+  }
+}
+```