[System.Runtime.InteropServices.DllImport("user32.dll")]        static extern int PostMessageA(IntPtr h, int msg, int wp, int lp);        void 文本_投递(IntPtr h,string str) {            byte[] b = Encoding.GetEncoding("gb2312").GetBytes(str);            for (int i = 0; i < b.Length; i++) {                PostMessageA(h, 258, b[i], 0);            }        }