QQ邮件发送

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.IO;
using System.Net.Mail;
using System.Text;
using System.Windows.Forms;

namespace WindowsFormsApplication3
{
    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 = txtneirong.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 = cbHost.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);
            }

        }
    }
}