C# - Programm aus ALT+TAB Liste verstecken

const int GWL_EXSTYLE = -20;
const int WS_EX_TOOLWINDOW = 0x00000080;

[DllImport("user32.dll")]
static extern int SetWindowLong(IntPtr hWnd, int nIndex, int dwNewLong);
        
[DllImport("user32.dll", SetLastError = true)]
static extern int GetWindowLong(IntPtr hWnd, int nIndex);


// verstecken durch diesen Aufruf
SetWindowLong(this.Handle, GWL_EXSTYLE, GetWindowLong(this.Handle, GWL_EXSTYLE) | WS_EX_TOOLWINDOW);