vs2005 下的发邮件代码

sendemail.aspx 

< body >
     < form  id ="form1"  runat ="server" >
         < div >
            发件人：
             < asp:TextBox  ID ="TextBox1"  runat ="server" ></ asp:TextBox >< br  />
            密码：
             < asp:TextBox  ID ="TextBox2"  runat ="server"  TextMode ="Password" ></ asp:TextBox >< br  />
            收件人：
             < asp:TextBox  ID ="TextBox3"  runat ="server" ></ asp:TextBox >< br  />
            主题：
             < asp:TextBox  ID ="TextBox4"  runat ="server" ></ asp:TextBox >< br  />
            内容：
             < asp:TextBox  ID ="TextBox5"  runat ="server"  TextMode ="MultiLine" ></ asp:TextBox >< br  />
            附件：
             < asp:FileUpload  ID ="FileUpload1"  runat ="server"   />< br  />
             < asp:Button  ID ="Button1"  runat ="server"  Text ="发送"   OnClick ="Button1_Click" />
         </ div >
     </ form >
</ body >

后台代码

using  System;
using  System.Data;
using  System.Configuration;
using  System.Collections;
using  System.Web;
using  System.Web.Security;
using  System.Web.UI;
using  System.Web.UI.WebControls;
using  System.Web.UI.WebControls.WebParts;
using  System.Web.UI.HtmlControls;
using  System.Net;
using  System.Net.Mail;
public  partial  class  sendemail : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {

    }
    protected void Button1_Click(object sender, EventArgs e)
    {
        string s_from = TextBox1.Text.Trim().ToString();
        string pwd = TextBox2.Text.Trim().ToString();
        string s_to = TextBox3.Text.Trim().ToString();

        string s_body = TextBox5.Text.Trim().ToString();
        //s_body = s_body.Replace("\r\n", "<br/>");
        //s_body = s_body.Replace("\n", "<br/>");
        //s_body = s_body.Replace(" ", "&nbsp");
        s_body = Server.HtmlEncode(s_body);
        int i = s_from.IndexOf("@");
        string username = s_from.Substring(0, i);

        //构建MailMessage对象
        MailAddress from = new MailAddress(s_from);
        MailAddress to = new MailAddress(s_to);
        MailMessage mailobj = new MailMessage(from, to);
        //完善MailMessage对象
        mailobj.Subject = TextBox4.Text.Trim().ToString();
        mailobj.Body = s_body;
        mailobj.IsBodyHtml = true;
        mailobj.BodyEncoding = System.Text.Encoding.GetEncoding("GB2312");
        mailobj.Priority = MailPriority.High;
        if (FileUpload1.PostedFile.ContentLength > 0)
            mailobj.Attachments.Add(new Attachment(FileUpload1.PostedFile.FileName));
        //构建SmtpClient对象
        SmtpClient smtp = new SmtpClient("smtp.163.com");// smtp.Host = "smtp.163.com";
        smtp.UseDefaultCredentials = false;
        smtp.Credentials = new NetworkCredential(username, pwd);
        smtp.DeliveryMethod = SmtpDeliveryMethod.Network;

        try
        {
            smtp.Send(mailobj);
            Response.Write("ok!");
        }
        catch
        {
            Response.Write("sorry!");
        }
    }
}