클로스 쓰레드

        private delegate void WritetextDelegate(string msg);

        public void Writetext(string msg)
        {
            try
            {
                if (this.InvokeRequired == false)
                {
                    textBox1.Text = msg;
                }
                else
                {
                    WritetextDelegate dd = new WritetextDelegate(Writetext);
                    object[] t = new object[] { msg };
                    this.BeginInvoke(dd, t);
                    //동기방식 
                    //this.Invoke(dd, t);
                }
            }
            catch (Exception er)
            {
                //Console.WriteLine(er.ToString());
                //MessageBox.Show(System.Diagnostics.Trace);
                System.Diagnostics.Trace.WriteLine(er.Message);
            }
        }