public static void SendWindowsStringMessage(int hWnd, int wParam, string msg)
{
if (hWnd <= 0) return;
byte[] sarr = Encoding.Default.GetBytes(msg);
int len = sarr.Length;
var cds = new CopyDataStruct {DwData = (IntPtr) 100, LpData = msg, CbData = len + 1};
SendMessage(hWnd, WM_COPYDATA, wParam, ref cds);
}
public static extern int PostMessage(int hWnd, int msg, int wParam, ref CopyDataStruct lParam);
private static extern int SendMessage(int hWnd, int msg, int wParam, ref CopyDataStruct lParam);
private static extern int SendMessage(int hWnd, int msg, int wParam, ref CopyDataStruct lParam);
