update docs

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

en/application-dev/reference/apis/Readme-EN.md

@@ -146,6 +146,8 @@
 
   - [@ohos.document](js-apis-document.md)
   - [@ohos.environment](js-apis-environment.md)
+  - [@ohos.data.fileAccess](js-apis-fileAccess.md)
+  - [@ohos.fileExtensionInfo](js-apis-fileExtensionInfo.md)
   - [@ohos.fileio](js-apis-fileio.md)
   - [@ohos.filemanagement.userfile_manager](js-apis-userfilemanager.md)
   - [@ohos.multimedia.medialibrary](js-apis-medialibrary.md)

en/application-dev/reference/apis/js-apis-fileExtensionInfo.md

+# User File Extension Info
+
+The **fileExtensionInfo** module defines attributes in **RootInfo** and **FileInfo** of the user file access and management module.
+
+>**NOTE**
+>
+>- The initial APIs of this module are supported since API version 9. Newly added APIs will be marked with a superscript to indicate their earliest API version.
+>- The APIs provided by this module are system APIs.
+
+## Modules to Import
+
+```js
+import fileExtensionInfo from '@ohos.fileExtensionInfo';
+```
+
+## fileExtensionInfo.DeviceType
+
+Defines the values of **deviceType** used in **RootInfo**.
+
+**System capability**: SystemCapability.FileManagement.UserFileService
+
+| Name| Value| Description|
+| ----- | ------ | ------ |
+| DEVICE_LOCAL_DISK | 1 | Local disk.|
+| DEVICE_SHARED_DISK | 2 | Shared disk.|
+| DEVICE_SHARED_TERMINAL | 3 | Distributed network device.|
+| DEVICE_NETWORK_NEIGHBORHOODS | 4 | Network neighbor device.|
+| DEVICE_EXTERNAL_MTP | 5 | MTP device.|
+| DEVICE_EXTERNAL_USB | 6 | USB device.|
+| DEVICE_EXTERNAL_CLOUD | 7 | Cloud disk.|
+
+## fileExtensionInfo.DeviceFlag
+
+Defines the values of **deviceFlags** used in **RootInfo**. **deviceFlags** is used to determine whether a capability is available through the AND operation.
+
+**System capability**: SystemCapability.FileManagement.UserFileService
+
+### Attributes
+
+  | Name| Type  | Value| Readable| Writable| Description    |
+  | ------ | ------ | ---- | ---- | ---- | -------- |
+  | SUPPORTS_READ   | number | 0b1 | Yes  | No  | Read support.|
+  | SUPPORTS_WRITE   | number | 0b10 | Yes  | No  | Write support.|
+
+## fileExtensionInfo.DocumentFlag
+
+Defines the values of **mode** used in **FileInfo**.
+
+**System capability**: SystemCapability.FileManagement.UserFileService
+
+### Attributes
+
+  | Name| Type  | Value| Readable| Writable| Description    |
+  | ------ | ------ | ---- | ---- | ---- | -------- |
+  | REPRESENTS_FILE   | number | 0b1 | Yes  | No  | File.|
+  | REPRESENTS_DIR   | number | 0b10 | Yes  | No  | Directory.|
+  | SUPPORTS_READ   | number | 0b100 | Yes  | No  | Read support.|
+  | SUPPORTS_WRITE   | number | 0b1000 | Yes  | No  | Write support.|