C#

// Text box code
public class SampleTextBox : TextBox
    {
        public SampleTextBox()
        {
            BorderStyle = BorderStyle.FixedSingle;
        }

        protected override void WndProc(ref Message m)
        {
            switch (m.Msg)
            {
                case 0x000F: // WM_PAINT
                    base.WndProc(ref m);
                        
                    Control control = Control.FromHandle(Handle);
                    Graphics g = Graphics.FromHwnd(Handle);

                    ControlPaint.DrawBorder(g, control.ClientRectangle, Color.YellowGreen, ButtonBorderStyle.Solid);
                  
                    g.Dispose();
                    break;                
                default:
                    base.WndProc(ref m);
                    break;
            }
        }
    }

// Form code

public class SampleForm : Form
    {
        public SampleForm()
        {
            BackColor = Color.SteelBlue;
        }

        protected override CreateParams CreateParams
        {
            get
            {
                CreateParams cp = base.CreateParams;
                cp.ExStyle |= 0x02000000; /*WS_EX_COMPOSITED*/
                return cp;
            }
        }
    }


public class Form2 : SampleForm
    {
        private SampleTextBox textbox1;

        public Form2()
        {

            textbox1 = new SampleTextBox();
            textbox1.Location = new Point(50, 50);

            this.Controls.Add(textbox1);

        }
    }

static CookieContainer cookieJar = new CookieContainer();

public string PostContenct(string dataPost, string srcuri)
       {
           Uri uri = new Uri(srcuri);
           string data = dataPost;
           //if (uri.Scheme == Uri.UriSchemeHttp)
           //{


            HttpWebRequest request = (HttpWebRequest)HttpWebRequest.Create(uri);
               request.CookieContainer = cookieJar;
               request.AllowAutoRedirect = true;
               request.Method = WebRequestMethods.Http.Post;
               request.ContentLength = data.Length;
               //request.AllowAutoRedirect = true;
               request.ContentType = "application/x-www-form-urlencoded";

               StreamWriter writer = new StreamWriter(request.GetRequestStream());
               writer.Write(data);
               writer.Close();

               HttpWebResponse response = (HttpWebResponse)request.GetResponse();
               int cookiecount = cookieJar.Count;
               StreamReader reader = new StreamReader(response.GetResponseStream());
               string str = response.StatusDescription;
               string tmp = reader.ReadToEnd();
               response.Close();
               return tmp;
           //}
           //else
           //{
           //    return "";
           //}

       }