source.cpp

#using <system.dll>
#using <System.Data.dll>
#using <System.Drawing.dll>
#using <system.windows.forms.dll>

usingnamespaceSystem;
usingnamespaceSystem::Data;
usingnamespaceSystem::ComponentModel;
usingnamespaceSystem::Windows::Forms;

public ref classForm1: publicForm
{
protected:
bool myDataIsSaved;

// <Snippet1>
private:
// Call this method from the InitializeComponent() method of your form
voidOtherInitialize()
 {
this->Closing += gcnew CancelEventHandler( this, &Form1::Form1_Cancel );
this->myDataIsSaved = true;
 }

voidForm1_Cancel( Object^ /*sender*/, CancelEventArgs^ e )
 {
if ( !myDataIsSaved )
 {
 e->Cancel = true;
MessageBox::Show( "You must save first." );
 }
else
 {
 e->Cancel = false;
MessageBox::Show( "Goodbye." );
 }
 }
// </Snippet1>
};