Sending Mail in C# Asp.net

Sending Mail in C# Asp.net

using System;
using System.Collections.Generic;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;


public partial class _Default : System.Web.UI.Page 
{
    protected void Page_Load(object sender, EventArgs e)
    {


    }
    protected void BtnSend_Click(object sender, EventArgs e)
    {
        System.Net.Mail.MailMessage obj = new System.Net.Mail.MailMessage();
        obj.From = new System.Net.Mail.MailAddress(TxtFrm.Text);
        if (TxtTo.Text.Contains(","))
        {
            string[] to = TxtTo.Text.Split(',');
            foreach (string r in to)
            {
                obj.To.Add(new System.Net.Mail.MailAddress(r));
            }
        }
        else
        {
            obj.To.Add(new System.Net.Mail.MailAddress(TxtTo.Text));
        }
        obj.CC.Add(new System.Net.Mail.MailAddress(TxtCc.Text));
        obj.Bcc.Add(new System.Net.Mail.MailAddress(TxtBCc.Text));
        obj.Subject = TxtSub.Text;
        obj.IsBodyHtml = true;
        System.Net.Mail.Attachment att = new System.Net.Mail.Attachment(FileUpload1.PostedFile.InputStream,FileUpload1.PostedFile.FileName,FileUpload1.PostedFile.ContentType);
        obj.Attachments.Add(att);
        obj.Body = Txtbdy.Text;
        System.Net.Mail.SmtpClient smtp = new System.Net.Mail.SmtpClient("1.0.0.0", 25);
        try
        {
            smtp.Send(obj);
        }
        catch (Exception ex)
        {
            Response.Redirect(ex.Message);
        }
    }
}