增加首选项错误码文档

Signed-off-by: Nduanweiling <duanweiling@huawei.com>

zh-cn/application-dev/reference/apis/js-apis-data-preferences.md

@@ -58,7 +58,6 @@ try {
 	        console.info("Failed to get preferences. code =" + err.code + ", message =" + err.message);
 	        return;
 	    }
-        preferences = object;
 	    console.info("Succeeded in getting preferences.");
 	})
 } catch (err) {
@@ -85,7 +84,6 @@ try {
 	        console.info("Failed to get preferences. code =" + err.code + ", message =" + err.message);
 	        return;
 	    }
-        preferences = object;
 	    console.info("Succeeded in getting preferences.");
 	})
 } catch (err) {
@@ -161,7 +159,6 @@ try{
 } catch(err) {
     console.log("Failed to get preferences. code =" + err.code + ", message =" + err.message);
 }
-
 ```
 
 ## data_preferences.deletePreferences
@@ -350,8 +347,9 @@ try {
             console.info("Failed to remove preferences. code =" + err.code + ", message =" + err.message);
             return;
         }
+        expect(true).assertEqual(val);
         console.info("Succeeded in removing preferences.");
-})
+    })
 } catch (err) {
     console.info("Failed to remove preferences. code =" + err.code + ", message =" + err.message);
 }
@@ -375,11 +373,13 @@ try {
             console.info("Failed to remove preferences. code =" + err.code + ", message =" + err.message);
             return;
         }
+        expect(true).assertEqual(val);
         console.info("Succeeded in removing preferences.");
-})
+    })
 } catch (err) {
     console.info("Failed to remove preferences. code =" + err.code + ", message =" + err.message);
 }
+
 ```
 
 ## data_preferences.removePreferencesFromCache
@@ -482,6 +482,7 @@ try {
             console.info("Failed to get value of 'startup'. code =" + err.code + ", message =" + err.message);
             return;
         }
+        expect(true).assertEqual(val);
         console.info("Succeeded in getting value of 'startup'. val： " + val);
     })
 } catch (err) {
@@ -555,7 +556,7 @@ try {
     })
 } catch (err) {
  console.info("Failed to get all key-values. code =" + err.code + ", message =" + err.message);
-};
+}
 ```
 
 
@@ -578,7 +579,7 @@ getAll(): Promise<Object>
 ```js
 try {
     let promise = preferences.getAll();
-promise.then((value) => {
+    promise.then((value) => {
     let allKeys = Object.keys(value);
     console.info('getAll keys = ' + allKeys);
     console.info("getAll object = " + JSON.stringify(value));
@@ -649,7 +650,7 @@ put(key: string, value: ValueType): Promise<void>
 ```js
 try{
     let promise = preferences.put('startup', 'auto');
-promise.then(() => {
+    promise.then(() => {
     console.info("Succeeded in putting value of 'startup'.");
     }).catch((err) => {
         console.info("Failed to put value of 'startup'. code =" + err.code +", message =" + err.message);
@@ -678,7 +679,7 @@ has(key: string, callback: AsyncCallback<boolean>): void
 **示例：**
 
 ```js
-    try{
+try{
     preferences.has('startup', function (err, val) {
     if (err) {
       console.info("Failed to check the key 'startup'. code =" + err.code + ", message =" + err.message);
@@ -719,7 +720,7 @@ has(key: string): Promise<boolean>
 **示例：**
 
 ```js
-    try{
+try{
     let promise = preferences.has('startup');
     promise.then((val) => {
         if (val) {
@@ -730,10 +731,9 @@ has(key: string): Promise<boolean>
     }).catch((err) => {
         console.info("Failed to check the key 'startup'. code =" + err.code + ", message =" + err.message);
   })
-    } catch(err) {
+} catch(err) {
   console.info("Failed to check the key 'startup'. code =" + err.code + ", message =" + err.message);
-    }
-
+}
 ```
 
 
@@ -855,7 +855,7 @@ flush(): Promise<void>
 ```js
 try {
     let promise = preferences.flush();
-promise.then(() => {
+    promise.then(() => {
     console.info("Succeeded in flushing.");
     }).catch((err) => {
         console.info("Failed to flush. code =" + err.code + ", message =" + err.message);
@@ -970,10 +970,10 @@ try {
                     console.info("Succeeded in flushing."); // observer will be called.
                 })
             })
-})
-} catch (error) {
+        })
+    } catch (err) {
         console.info("Failed to flush. code =" + err.code + ", message =" + err.message);
-}
+    }
 ```
 
 
@@ -996,7 +996,7 @@ off(type: 'change', callback?: Callback<{ key : string }>): void
 
 ```js
 try {
-data_preferences.getPreferences(this.context, 'mystore', function (err, preferences) {
+    data_preferences.getPreferences(this.context, 'mystore', function (err, preferences) {
         if (err) {
             console.info("Failed to get preferences.");
             return;
@@ -1021,8 +1021,8 @@ data_preferences.getPreferences(this.context, 'mystore', function (err, preferen
             })
             preferences.off('change', observer);
         })
-})
-} catch (error) {
+    })
+} catch (err) {
     console.info("Failed to flush. code =" + err.code + ", message =" + err.message);}
 ```
 

zh-cn/application-dev/reference/errorcodes/errorcode-preferences.md

@@ -8,7 +8,9 @@ Failed to delete preferences.
 删除首选项失败。
 
 **可能原因**<br>
-系统错误导致文件删除失败。
+系统错误导致文件删除失败，可能原因如下：
+1. 要删除的文件不存在。
+2. 没有操作权限。
 
 **处理步骤**<br>
 重启设备后再次尝试。
\ No newline at end of file