message

        private void button1_Click(object sender, EventArgs e)
        {
            byte[] bBuffer = System.Text.Encoding.Unicode.GetBytes(textBox2.Text);
            int nRet = NetMessageBufferSend(null, textBox1.Text, null, textBox2.Text, textBox2.Text.Length * 2 + 2);
        }

        [DllImport("Netapi32", CharSet = CharSet.Unicode)]
        public static extern int NetMessageBufferSend(
         string servername, //服务器名称，为NULL
         string fromname, //接收方名称，可为IP或计算机名称
         string msgname, //信息名称，为NULL
         string buf, //信息
         int buflen); //信息长度