public void MouseCliceBackGround(IntPtr hwnd, int x, int y)
{
int WM_LBUTTONDOWN = 0x201; //按下
int WM_LBUTTONUP = 0x202; //弹起
System.Drawing.Point point = new System.Drawing.Point(x, y);
User32API.SendMessageA(hwnd, WM_LBUTTONDOWN, point.X, point.Y);
User32API.SendMessageA(hwnd, WM_LBUTTONUP, point.X, point.Y);
}