Here is an example that tests for the escape key being pressed while a form is active.
You need to be more specific.
protected override bool ProcessCmdKey(ref Message msg, Keys keyData)
{
const int WM_KEYDOWN = 0x100;
if (msg.Msg == WM_KEYDOWN)
{
if (keyData == Keys.Escape)
{
DialogResult = DialogResult.Cancel;
this.Dispose();
return true;
}
}
return base.ProcessCmdKey(ref msg, keyData);
}