update zh-cn/application-dev/ability/fa-pageability.md.

Signed-off-by: Nql <qianli16@huawei.com>

zh-cn/application-dev/ability/fa-pageability.md

@@ -131,7 +131,7 @@ PageAbility提供命周期回调，开发者可以在`app.js/app.ets`中重写
   function onStartRemoteAbility() {
   console.info('onStartRemoteAbility begin');
   let params;
-  var wantValue = {
+  let wantValue = {
     bundleName: 'ohos.samples.etsDemo',
     abilityName: 'ohos.samples.etsDemo.RemoteAbility',
     deviceId: getRemoteDeviceId(),
@@ -153,7 +153,7 @@ PageAbility提供命周期回调，开发者可以在`app.js/app.ets`中重写
   let dmClass;
   function getRemoteDeviceId() {
     if (typeof dmClass === 'object' && dmClass != null) {
-        var list = dmClass.getTrustedDeviceListSync();
+        let list = dmClass.getTrustedDeviceListSync();
         if (typeof (list) == 'undefined' || typeof (list.length) == 'undefined') {
             console.log("MainAbility onButtonClick getRemoteDeviceId err: list is null");
             return;
@@ -173,15 +173,15 @@ PageAbility提供命周期回调，开发者可以在`app.js/app.ets`中重写
   async function RequestPermission() {
   console.info('RequestPermission begin');
   let array: Array<string> = ["ohos.permission.DISTRIBUTED_DATASYNC"];
-  var bundleFlag = 0;
-  var tokenID = undefined;
-  var userID = 100;
-  var appInfo = await bundle.getApplicationInfo('ohos.samples.etsDemo', bundleFlag, userID);
+  let bundleFlag = 0;
+  let tokenID = undefined;
+  let userID = 100;
+  let  appInfo = await bundle.getApplicationInfo('ohos.samples.etsDemo', bundleFlag, userID);
   tokenID = appInfo.accessTokenId;
-  var atManager = abilityAccessCtrl.createAtManager();
+  let atManager = abilityAccessCtrl.createAtManager();
   let requestPermissions: Array<string> = [];
   for (let i = 0;i < array.length; i++) {
-    var result = await atManager.verifyAccessToken(tokenID, array[i]);
+    let result = await atManager.verifyAccessToken(tokenID, array[i]);
     console.info("verifyAccessToken result:" + JSON.stringify(result));
     if (result == abilityAccessCtrl.GrantStatus.PERMISSION_GRANTED) {
     } else {