!2348 Done! 2013:config_policy增加api说明

Merge pull request !2348 from wusongqing/TR2013

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

@@ -110,4 +110,6 @@
     -   [Nonlinear Container TreeSet](js-apis-treeset.md)
     -   [Nonlinear Container LightWeightMap](js-apis-lightweightmap.md)
     -   [Nonlinear Container LightWeightSet](js-apis-lightweightset.md)
+- Custom Management
+    -   [Configuration Policy](js-apis-config-policy.md)
 

en/application-dev/reference/apis/js-apis-config-policy.md

+# Configuration Policy
+
+> ![icon-note.gif](public_sys-resources/icon-note.gif) **NOTE**
+> - The initial APIs of this module are supported since API version 8. 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.
+
+The configuration policy provides the capability of obtaining the custom configuration directory and file path based on the predefined custom configuration level.
+
+## Modules to Import
+
+```
+import configPolicy from '@ohos.configPolicy';
+```
+
+## getOneCfgFile
+
+getOneCfgFile(relPath: string, callback: AsyncCallback<string>): void
+
+Obtains the path of a configuration file with the specified name and highest priority. This API uses an asynchronous callback to return the result.
+For example, if the **config.xml** file is stored in **/system/etc/config.xml** and **/sys-pod/etc/config.xml** (in ascending order of priority), then **/sys-pod/etc/config.xml** is returned.
+
+**System capability**: SystemCapability.Customization.ConfigPolicy
+
+**Parameters**
+  | Name| Type| Mandatory| Description|
+  | -------- | -------- | -------- | -------- |
+  | relPath | string | Yes| Name of the configuration file.|
+  | callback | AsyncCallback<string> | Yes| Callback used to return the path of the configuration file.|
+
+**Example**
+  ```
+  configPolicy.getOneCfgFile('config.xml', (error, value) => {
+      if (error == undefined) {
+          console.log(value);
+      } else {
+          console.log(error);
+      }
+  });
+  ```
+
+
+## getOneCfgFile
+
+getOneCfgFile(relPath: string): Promise<string>
+
+Obtains the path of a configuration file with the specified name and highest priority. This API uses a promise to return the result.
+
+**System capability**: SystemCapability.Customization.ConfigPolicy
+
+**Parameters**
+  | Name| Type| Mandatory| Description|
+  | -------- | -------- | -------- | -------- |
+  | relPath | string | Yes| Name of the configuration file.|
+
+**Return value**
+  | Type| Description|
+  | -------- | -------- |
+  | Promise<string> | Promise used to return the path of the configuration file.|
+
+**Example**
+  ```
+  configPolicy.getOneCfgFile('config.xml').then(value => {
+      console.log(value);
+  }).catch(error => {
+      console.log("getOneCfgFile promise " + error);
+  });
+  ```
+
+
+## getCfgFiles
+
+getCfgFiles(relPath: string, callback: AsyncCallback<Array<string>>): void
+
+Obtains all configuration files with the specified name and lists them in ascending order of priority. This API uses an asynchronous callback to return the result. For example, if the **config.xml** file is stored in **/system/etc/config.xml**
+and **/sys-pod/etc/config.xml**, then **/system/etc/config.xml, /sys-pod/etc/config.xml** is returned.
+
+**System capability**: SystemCapability.Customization.ConfigPolicy
+
+**Parameters**
+  | Name| Type| Mandatory| Description|
+  | -------- | -------- | -------- | -------- |
+  | relPath | string | Yes| Name of the configuration file.|
+  | callback | AsyncCallback<Array<string>> | Yes| Callback used to return the file list.|
+
+**Example**
+  ```
+  configPolicy.getCfgFiles('config.xml', (error, value) => {
+      if (error == undefined) {
+          console.log(value);
+      } else {
+          console.log(error);
+      }
+  });
+  ```
+
+
+## getCfgFiles
+
+getCfgFiles(relPath: string): Promise<Array<string>>
+
+Obtains all configuration files with the specified name and lists them in ascending order of priority. This API uses a promise to return the result.
+
+**System capability**: SystemCapability.Customization.ConfigPolicy
+
+**Parameters**
+  | Name| Type| Mandatory| Description|
+  | -------- | -------- | -------- | -------- |
+  | relPath | string | Yes| Name of the configuration file.|
+
+**Return value**
+  | Type| Description|
+  | -------- | -------- |
+  | Promise<Array<string>> | Promise used to return the file list.|
+
+**Example**
+  ```
+  configPolicy.getCfgFiles('config.xml').then(value => {
+      console.log(value);
+  }).catch(error => {
+      console.log("getCfgFiles promise " + error);
+  });
+  ```
+
+
+## getCfgDirList
+
+getCfgDirList(callback: AsyncCallback<Array<string>>): void
+
+Obtains the configuration level directory list. This API uses an asynchronous callback to return the result.
+
+**System capability**: SystemCapability.Customization.ConfigPolicy
+
+**Parameters**
+  | Name| Type| Mandatory| Description|
+  | -------- | -------- | -------- | -------- |
+  | callback | AsyncCallback<Array<string>> | Yes| Callback used to return the configuration level directory list.|
+
+**Example**
+  ```
+  configPolicy.getCfgDirList((error, value) => {
+      if (error == undefined) {
+          console.log(value);
+      } else {
+          console.log(error);
+      }
+  });
+  ```
+
+
+## getCfgDirList
+
+getCfgDirList(): Promise<Array<string>>
+
+Obtains the configuration level directory list. This API uses a promise to return the result.
+
+**System capability**: SystemCapability.Customization.ConfigPolicy
+
+**Return value**
+  | Type| Description|
+  | -------- | -------- |
+  | Promise<Array<string>> | Promise used to return the configuration level directory list.|
+
+**Example**
+  ```
+  configPolicy.getCfgDirList().then(value => {
+      console.log(value);
+  }).catch(error => {
+      console.log("getCfgDirList promise " + error);
+  });
+  ```