c# 发送邮件

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.Net.Mail;

namespace WindowsFormsApplication1
{
public partial class Form1 : Form
    {
public Form1()
        {
InitializeComponent();
        }

private void button1_Click(object sender, EventArgs e)
        {
System.Net.Mail.SmtpClient client = new SmtpClient("smtp.qq.com");

client.UseDefaultCredentials = false;
client.Credentials = new System.Net.NetworkCredential("[e-mail]", "yyyyy");
client.DeliveryMethod = SmtpDeliveryMethod.Network;

MailAddress addressFrom = new MailAddress("[e-mail]", "xxxx");
MailAddress addressTo = new MailAddress("[e-mail]", "test");

System.Net.Mail.MailMessage message = new MailMessage(addressFrom, addressTo);
message.Sender = new MailAddress("[e-mail]");
message.BodyEncoding = System.Text.Encoding.UTF8;
message.IsBodyHtml = true;
message.Subject = "test";

client.Send(message); 

        }

    }
}