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CancelEventArgs::Cancel Property

 

Gets or sets a value indicating whether the event should be canceled.

Namespace:   System.ComponentModel
Assembly:  System (in System.dll)

public:
property bool Cancel {
	bool get();
	void set(bool value);
}

Property Value

Type: System::Boolean

true if the event should be canceled; otherwise, false.

The following example uses CancelEventArgs and a CancelEventHandler to handle the FormClosing event of a Form. This code assumes that you have created a Form with a class-level Boolean variable named isDataSaved. It also assumes that you have added a statement to invoke the OtherInitialize method from the form's Load method or the constructor (after the call to InitializeComponent).

private:
   // Call this method from the InitializeComponent() method of your form
   void OtherInitialize()
   {
      this->Closing += gcnew CancelEventHandler( this, &Form1::Form1_Cancel );
      this->myDataIsSaved = true;
   }

   void Form1_Cancel( Object^ /*sender*/, CancelEventArgs^ e )
   {
      if ( !myDataIsSaved )
      {
         e->Cancel = true;
         MessageBox::Show( "You must save first." );
      }
      else
      {
         e->Cancel = false;
         MessageBox::Show( "Goodbye." );
      }
   }

Universal Windows Platform
Available since 8
.NET Framework
Available since 1.1
Portable Class Library
Supported in: portable .NET platforms
Silverlight
Available since 3.0
Windows Phone Silverlight
Available since 7.0
Windows Phone
Available since 8.1
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