diff --git a/en/application-dev/reference/arkui-ts/ts-methods-custom-dialog-box.md b/en/application-dev/reference/arkui-ts/ts-methods-custom-dialog-box.md
index 37bf4de513a5773e660b53d8a07c621882c21714..2aef524442b5684e2a509565e642033f50f6cd06 100644
--- a/en/application-dev/reference/arkui-ts/ts-methods-custom-dialog-box.md
+++ b/en/application-dev/reference/arkui-ts/ts-methods-custom-dialog-box.md
@@ -108,6 +108,11 @@ struct CustomDialogUser {
     customStyle: false
   })
 
+  aboutToDisappear() {
+    delete this.dialogController,
+    this.dialogController = undefined
+  }
+
   onCancel() {
     console.info('Callback when the first button is clicked')
   }
@@ -124,7 +129,9 @@ struct CustomDialogUser {
     Column() {
       Button(this.inputValue)
         .onClick(() => {
-          this.dialogController.open()
+          if (this.dialogController != undefined) {
+            this.dialogController.open()
+          }
         }).backgroundColor(0x317aff)
     }.width('100%').margin({ top: 5 })
   }