源码共享：ASP.NET发电子邮件源码---流行第一线

using System.Collections.Generic;

using System.Text;
using System.Net;
using System.Net.Mail;

try
{
//编码暂硬性规定为GB2312
Encoding encoding = Encoding.GetEncoding(936);
MailMessage Message = new MailMessage(
new MailAddress("自己的邮箱", "5", encoding),//第一个是发信人的地址，第二个参数是发信人
new MailAddress(TextBox1.Text));//收信人邮箱

Message.SubjectEncoding = encoding;
Message.Subject =TextBox2.Text;//标题
Message.BodyEncoding = encoding;
Message.Body = TextBox3.Text; //主体
SmtpClient smtpClient = new SmtpClient("smtp.163.com");//信箱服务器
smtpClient.Credentials = new NetworkCredential("自己的邮箱用户名", "自己的邮箱密码");//信箱的用户名和密码
smtpClient.Timeout = 999999;
smtpClient.Send(Message);
}
catch (Exception ex)
{
throw new Exception(ex.Message);
}