update ts-components-canvas-canvasgradient.md (8035)

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

en/application-dev/reference/arkui-ts/ts-components-canvas-canvasgradient.md

 # CanvasGradient
 
 
-> **NOTE**<br>
+> **NOTE**
+>
 > This component is supported since API version 8. Updates will be marked with a superscript to indicate their earliest API version.
 
 
@@ -18,11 +19,12 @@ Adds a color stop for the **CanvasGradient** object based on the specified offse
   | Name | Type | Mandatory | Default Value | Description |
   | -------- | -------- | -------- | -------- | -------- |
   | offset   | number   | Yes      | 0        | Proportion of the distance between the color stop and the start point to the total length. The value ranges from 0 to 1. |
-  | color | string | Yes | 'ffffff' | Gradient color to set. |
+  | color    | string   | Yes      | '#ffffff'| Gradient color to set. |
 
 - Example
   
-  ```
+  ```ts
+  // xxx.ets
   @Entry
   @Component
   struct Page45 {
@@ -37,9 +39,9 @@ Adds a color stop for the **CanvasGradient** object based on the specified offse
           .backgroundColor('#ffff00')
           .onReady(() =>{
             var grad = this.context.createLinearGradient(50,0, 300,100)
-            this.grad.addColorStop(0.0, 'red')
-            this.grad.addColorStop(0.5, 'white')
-            this.grad.addColorStop(1.0, 'green')
+            grad.addColorStop(0.0, 'red')
+            grad.addColorStop(0.5, 'white')
+            grad.addColorStop(1.0, 'green')
             this.context.fillStyle = grad
             this.context.fillRect(0, 0, 500, 500)
           })