How do I listen to windows messages in my Control?

In a derived class you should override WndProc as follows (listening to the WM_KEYUP message, for example):

[C#]
public class MyCombo : ComboBox
{
         private const int WM_KEYUP = 0x101;

         protected override void WndProc(ref System.Windows.Forms.Message m)
         {
                  if(m.Msg == WM_KEYUP)
                  {
                           return;  //ignore the keyup
                  }
                  base.WndProc(ref m);
         }
}

[VB.NET]
Public Class MyTextBox
	Inherits TextBox
	Private WM_KEYUP As Integer = &H101
 
	Protected Overrides Sub WndProc(ByRef m As System.Windows.Forms.Message)
		If m.Msg = WM_KEYUP Then
			Return ’ignore the keyup
		End If
		MyBase.WndProc(m)
	End Sub ’WndProc
End Class ’MyTextBox