將視窗關閉按鈕轉換為「最小化」

遮蔽 Form WndProc 事件 並撰寫以下程式即可

protected override void WndProc(ref Message m)
{
const int WM_SYSCOMMAND = 0x0112;
const int SC_CLOSE = 0xF060;

if (m.Msg == WM_SYSCOMMAND && (int)m.WParam == SC_CLOSE)
{
// User clicked close button
this.WindowState = FormWindowState.Minimized;
return;
}

base.WndProc(ref m);
}