winform实现邮件的发送（带附件）

 
using System;

using System.Collections.Generic;

using System.ComponentModel;

using System.Data;

using System.Drawing;

using System.Linq;

using System.Text;

using System.Windows.Forms;

using System.Net.Mail;

using System.Net;

namespace mailTest

{

    public partial class Form1 : Form

    {

        public Form1()

        {

            InitializeComponent();

        }

        private void button1_Click(object sender, EventArgs e)

        {

            MailMessage msg = new MailMessage();

            msg.Body = this.textBox3.Text;

            msg.From = new MailAddress(*****@163.com); //   发送的邮件地址（主机）

            //msg.Sender = new MailAddress("");

            msg.To.Add("3@qq.com");                                          //要接受的邮件地址

            msg.Subject = this.textBox2.Text;

            msg.IsBodyHtml = true;                         //邮件内容默认是纯文本！如果指定html内容，需要使用isbodyHtml

            SmtpClient sc = new SmtpClient();

            sc.Host = "smtp.163.com";                 //这个不一定是163，看你的主机的邮箱型号，还可以是smtp.qq.com, smtp.126.com , smtp.yahoo.com 等等

            sc.Port = 25;

            NetworkCredential nc = new NetworkCredential();

            nc.UserName = "******";       //主机的邮箱名称

            nc.Password = "********";     //主机的邮箱密码

            sc.Credentials = nc;

            Attachment att = new Attachment(this.textBox4.Text);

            msg.Attachments.Add(att);

            sc.Send(msg);

            MessageBox.Show("发送成功！");

        }

        private void button2_Click(object sender, EventArgs e)

        {

            if (this.openFileDialog1.ShowDialog() ==System.Windows.Forms.DialogResult.OK)

            {

                this.textBox4.Text = this.openFileDialog1.FileName;           //上传附件，打开对话框，得到客户端的文件

            }

        }

    }

}