update docs

Signed-off-by: Nester.zhou <ester.zhou@huawei.com>

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

@@ -169,9 +169,9 @@ Publishes a common event with given attributes. This method uses a callback to r
 ```js
 // Attributes of a common event.
 var options = {
-	code: 0;			 // Result code of the common event
-	data: "initial data";// Result data of the common event
-	isOrdered: true;	 // The common event is an ordered one.
+	code: 0,			 // Result code of the common event
+	data: "initial data",// Result data of the common event
+	isOrdered: true 	 // The common event is an ordered one.
 }
 // Callback for common event publication
 function PublishCallBack(err) {

en/application-dev/reference/arkui-js/js-components-canvas-image.md

@@ -89,7 +89,7 @@
 export default {
   onShow(){
     const el =this.$refs.canvas
-    var ctx = this.$element('drawImage').getContext('2d');
+    var ctx =el.getContext('2d');
     var img = new Image();
     img.src = 'common/images/example.jpg';
     img.onload = function() {