update docs

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

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

+# Volume Management
+
+> ![icon-note.gif](public_sys-resources/icon-note.gif) **NOTE**<br/>
+>
+> - 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 of this module are system APIs and cannot be called by third-party applications.
+
+## Modules to Import
+
+```js
+import volumemanager from "@ohos.volumeManager";
+```
+
+## volumemanager.getAllVolumes
+
+getAllVolumes(): Promise&lt;Array&lt;Volume&gt;&gt;
+
+Asynchronously obtains information about all available volumes. This method uses a promise to return the result.
+
+**System capability**: SystemCapability.FileManagement.StorageService.Volume
+
+- Return value
+
+  | Type                              | Description                      |
+  | ---------------------------------- | -------------------------- |
+  | Promise&lt;[Volume](#volume)[]&gt; | Promise used to return the execution result.|
+
+- Example
+
+  ```js
+  volumemanager.getAllVolumes().then(function(volumes){
+      // do something
+  });
+  ```
+
+## volumemanager.getAllVolumes
+
+getAllVolumes(callback: AsyncCallback&lt;Array&lt;Volume&gt;&gt;): void
+
+Asynchronously obtains information about all available volumes. This method uses a callback to return the result.
+
+**System capability**: SystemCapability.FileManagement.StorageService.Volume
+
+- Parameters
+
+  | Name  | Type                                             | Mandatory| Description                                |
+  | -------- | ------------------------------------------------- | ---- | ------------------------------------ |
+  | callback | callback:AsyncCallback&lt;[Volume](#volume)[]&gt; | Yes  | Callback invoked to return the volume information obtained.|
+  
+- Example
+
+  ```js
+  let uuid = "";
+  volumemanager.getAllVolumes(uuid, function(error, volumes){
+      // do something
+  });
+  ```
+
+
+## volumemanager.mount
+
+mount(volumeId: string): Promise&lt;boolean&gt;
+
+Asynchronously mounts a volume. This method uses a promise to return the result.
+
+**System capability**: SystemCapability.FileManagement.StorageService.Volume
+
+- Parameters
+
+  | Name  | Type  | Mandatory| Description|
+  | -------- | ------ | ---- | ---- |
+  | volumeId | string | Yes  | Volume ID.|
+
+- Return value
+
+  | Type                  | Description      |
+  | ---------------------- | ---------- |
+  | Promise&lt;boolean&gt; | Promise used to return the execution result.|
+
+- Example
+
+  ```js
+  let volumeId = "";
+  volumemanager.mount(volumeId).then(function(flag){
+      // do something
+  });
+  ```
+
+## volumemanager.mount
+
+mount(volumeId: string, callback:AsyncCallback&lt;boolean&gt;):void
+
+Asynchronously obtains the available space of the specified volume. This method uses a callback to return the result.
+
+**System capability**: SystemCapability.FileManagement.StorageService.Volume
+
+- Parameters
+
+  | Name  | Type                                 | Mandatory| Description                |
+  | -------- | ------------------------------------- | ---- | -------------------- |
+  | volumeId | string                                | Yes  | Volume ID.                |
+  | callback | callback:AsyncCallback&lt;boolean&gt; | Yes  | Callback invoked to return the execution result.|
+
+- Example
+
+  ```js
+  let volumeId = "";
+  volumemanager.mount(volumeId, function(error, flag){
+      // do something
+  });
+  ```
+
+## volumemanager.unmount
+
+unmount(volumeId: string): Promise&lt;boolean&gt;
+
+Asynchronously unmounts a volume. This method uses a promise to return the result.
+
+**System capability**: SystemCapability.FileManagement.StorageService.Volume
+
+- Parameters
+
+  | Name  | Type  | Mandatory| Description|
+  | -------- | ------ | ---- | ---- |
+  | volumeId | string | Yes  | Volume ID.|
+
+- Return value
+
+  | Type                  | Description      |
+  | ---------------------- | ---------- |
+  | Promise&lt;boolean&gt; | Promise used to return the execution result.|
+
+- Example
+
+  ```js
+  let volumeId = "";
+  volumemanager.unmount(volumeId).then(function(flag){
+      // do something
+  });
+  ```
+
+## volumemanager.unmount
+
+unmount(volumeId: string, callback:AsyncCallback&lt;boolean&gt;):void
+
+Asynchronously unmounts a volume. This method uses a callback to return the result.
+
+**System capability**: SystemCapability.FileManagement.StorageService.Volume
+
+- Parameters
+
+  | Name  | Type                                 | Mandatory| Description                |
+  | -------- | ------------------------------------- | ---- | -------------------- |
+  | volumeId | string                                | Yes  | Volume ID.                |
+  | callback | callback:AsyncCallback&lt;boolean&gt; | Yes  | Callback invoked to return the execution result.|
+
+- Example
+
+  ```js
+  let volumeId = "";
+  volumemanager.unmount(volumeId, function(error, flag){
+      // do something
+  });
+  ```
+
+## Volume
+
+**System capability**: SystemCapability.FileManagement.StorageService.Volume
+
+### Attributes
+
+| Name       | Type   | Description                |
+| ----------- | ------- | -------------------- |
+| id          | number  | Volume ID.                |
+| uuid        | string  | Universally unique identifier (UUID) of the volume.              |
+| description | string  | Description of the volume.          |
+| removable | boolean | Whether the volume is a removable storage device.|
+| state       | int     | Current volume status.          |
+| path        | string  | Mount address of the volume.        |