163及qq邮箱发送

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.IO;
using System.Linq;
using System.Net;
using System.Net.Mail;
using System.Text;
using System.Text.RegularExpressions;
using System.Threading.Tasks;
using System.Windows.Forms;

namespace WindowsFormsApplication1
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }
        //public static string CreateTimeoutTestMessage(string server)
        //{
        //    string Success = "发送成功";
        //    try
        //    {
        //        string _to = "[email protected]";
        //        string _from = "[email protected]";
        //        string _subject = "Using the new SMTP client.";
        //        string _body = @"Using this new feature, you can send an e-mail message from an application very easily.";
        //        MailMessage message = new MailMessage();
        //        message.From = new MailAddress(_from);
        //        //可以利用MailMessage.To.Add方法增加要发送的邮件地址
        //        message.To.Add(new MailAddress("[email protected]"));
        //        message.To.Add(new MailAddress(_to));
        //        message.Subject = _subject;
        //        message.Body = _body;

        //        //添加附件
        //        Attachment a = new Attachment(@"C:/Users/Administrator/Desktop/kk.txt");
        //        message.Attachments.Add(a);
        //        //设置邮箱的地址或IP
        //        SmtpClient client = new SmtpClient(server);
        //        //设置邮箱端口，pop3端口:110, smtp端口是:25
        //        client.Port = 25;

        //        //设置超时时间
        //        client.Timeout = 9999;

        //        //要输入邮箱用户名与密码  

        //        client.Credentials = new NetworkCredential("[email protected]", "zddszx");
        //        client.Send(message);
        //    }
        //    catch (Exception ex)
        //    {
        //        Success = ex.ToString();
        //    }
        //    return Success;
        //}

        private void button1_Click(object sender, EventArgs e)
        {
            string fuwuqi = textBox1.Text;
            string zhanghao = textBox2.Text;
            string mima = textBox3.Text;
            string dizhi = textBox4.Text;
            string biaoti = textBox5.Text;
            string neirong = textBox6.Text;
            SendMail(fuwuqi, zhanghao, mima, dizhi, biaoti, neirong);
        }
        public static void SendMail(string fuwuqi, string zhanghao, string mima, string dizhi, string biaoti, string neirong)
        {
            SmtpClient client = new SmtpClient(fuwuqi);    //邮件类，造一个对象client
            client.Credentials = new System.Net.NetworkCredential(zhanghao, mima);  //验证身份，通过发件人的地址和密码
            client.DeliveryMethod = SmtpDeliveryMethod.Network;  //指定如何发送电子邮件
            System.Net.Mail.MailMessage message = new MailMessage(zhanghao, dizhi, biaoti, neirong);
            message.BodyEncoding = System.Text.Encoding.UTF8;  //字符编码为Utf8
            message.IsBodyHtml = true;  //发送格式为html格式
            try
            {
                client.Send(message);  //讲指定的邮件发送到SMTP服务器以便传递
                MessageBox.Show("发送成功");
            }
            catch (Exception ex)
            {
                MessageBox.Show("错误信息：" + ex.Message, "错误");
            }
        }

        private void Form1_Load(object sender, EventArgs e)
        {
            textBox1.Text = "smtp.163.com";
            textBox2.Text = "[email protected]";
            textBox3.Text = "zddszx";
            textBox4.Text = "[email protected]";
        }

        private void button2_Click(object sender, EventArgs e)
        {
            string fuwuqi = textBox1.Text;   //服务器
            string mima = textBox3.Text;
            string biaoti = textBox5.Text;    //邮件标题
            string neirong = textBox6.Text;   //邮件的内容

            for (int i = 0; i < listView1.SelectedItems.Count; i++)
            {
                string dizhi = listView1.SelectedItems[i].SubItems[1].ToString();//收件地址
                string zhanghao = listView1.SelectedItems[i].SubItems[2].ToString();
                //string mima = listView1.SelectedItems[i].SubItems[3].ToString();
                SendMail(fuwuqi, zhanghao, mima, dizhi, biaoti, neirong);  //调用发送邮件方法需要输入六个参数
                System.Threading.Thread.Sleep(2000);
            }
        }
        int a = 0;
        private void button3_Click(object sender, EventArgs e)
        {
            listView1.Columns.Clear();
            listView1.Columns.Add("编号");
            listView1.Columns.Add("收件邮箱", 120);
            listView1.Columns.Add("发件箱", 120);
            //listView1.Columns.Add("密码", 120);
            listView1.GridLines = true;
            for (int i = 1; i <= 100; i++)
            {
                listView1.Items.Add("" + i);
            }
            listView1.Items[a].SubItems.Add(textBox4.Text);
            listView1.Items[a].SubItems.Add(textBox2.Text);
            listView1.Items[a].SubItems.Add(textBox3.Text);
            a++;
        }
    }
}

发送邮件的邮箱要先启用SMTP，否则不能发送

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using System.IO;
using System.Net.Mail;

namespace WindowsFormsApplication2
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void btnfasong_Click(object sender, EventArgs e)
        {
            try
            {
                MailAddress EmailFrom = new MailAddress(txtsend.Text);  //发件人邮箱地址
                string EmailTo = txtto.Text;  //收件人邮箱地址
                string Emailbiaoti = txtbiaoti.Text; //邮件标题
                string Emailneirong = txtnrong.Text; //邮件内容
                fasong(EmailTo, Emailbiaoti, Emailneirong, EmailFrom);
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message);
            }
        }
        public void fasong(string EmailTo, string Emailbiaoti, string Emailneirong, MailAddress EmailFrom)
        {

            try
            {
                txtto.Text = txtto.Text.Replace(" ", "");//去除空格
                txtto.Text = txtto.Text.Trim();
                MailMessage email = new MailMessage();
                email.From = EmailFrom;
                email.To.Add(EmailTo);//收件人邮箱地址可以是多个以实现群发
                email.Subject = Emailbiaoti;//获取邮件的标题
                email.Body = Emailneirong;//获取邮件的内容
                email.IsBodyHtml = false; //是否为html格式
                email.Priority = MailPriority.Normal;  //发送邮件的优先等级
                SmtpClient sc = new SmtpClient();//允许使用SMTP协议发送邮件
                sc.Host =txthost.Text;//指定发送邮件的服务器地址
                sc.Port = 25;//指定发送邮件端口
                sc.DeliveryMethod = SmtpDeliveryMethod.Network;//指定如何发送电子邮件，通过网络发送到SMTP服务器
                sc.UseDefaultCredentials = false;//是否随请求一起发送
                sc.EnableSsl = false;//安全连接设置
                sc.Credentials = new System.Net.NetworkCredential(txtsend.Text, txtsenderpwd.Text); //指定登录服务器的用户名和密码
                sc.Send(email);
                MessageBox.Show("发送成功!");
            }
            catch (Exception e)
            {
                MessageBox.Show(e.Message);
            }

        }

        private void Form1_Load(object sender, EventArgs e)
        {
            txthost.Text = "smtp.qq.com";
            txtsend.Text = "[email protected]";
            txtsenderpwd.UseSystemPasswordChar = true;
        }
    }
}