[DllImport("user32",EntryPoint="SetWindowLong")]
private static extern uint SetWindowLong(IntPtr hwnd,int nIndex,uint dwNewLong);
[DllImport("user32",EntryPoint="GetWindowLong")]
private static extern uint GetWindowLong(IntPtr hwnd,int nIndex);
const int GWL_EXSTYLE=-20;
private void CanPenetrate(){
uint intExTemp=GetWindowLong(this.handle,GWL_EXSTYLE);
uint oldGWLEx=SetWindowLong(this.handle,GWL_EXSTYLE,WS_EX_TRANSPARENT|WS_EX_LAYERED);
}
private void Form1_Load(object sender,EventArgs e)
{
this.ShowInTaskBar =false;
CanPenetrate()
this.TopMost=true;
}