C#编程实现发送邮件的方法(可添加附件)

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;
namespace WindowsFormsApplication63
{
 public partial class Form1 : Form
 {
  public Form1()
  {
   InitializeComponent();
  }
  //打开上传附件的对话框
  private void btnUP_Click(object sender, EventArgs e)
  {
   oFDialogSFile.InitialDirectory = "C:\";//设置对话框的初始目录为C盘
    oFDialogSFile.Filter = "all files (*.*)|*.*";//筛选字符串为所有文件
    oFDialogSFile.RestoreDirectory = true;
   oFDialogSFile.ShowDialog();
   cboxAccessories.Items.Add(oFDialogSFile.FileName.Trim());//当选择好文件后将文件名赋值给下拉框
  }
  //发送邮件
  private void btnSend_Click(object sender, EventArgs e)
  {
    try
    {
     string file = Application.StartupPath + "testXML.xml";
     //SmtpClient下的一个对象，用以设置邮件的主题和内容
      System.Net.Mail.MailMessage myMail = new System.Net.Mail.MailMessage();
     //发送端到接收端的邮箱地址
      myMail = new System.Net.Mail.MailMessage(txtSEmail.Text.Trim(), txtCEmail.Text.Trim());
     myMail.Subject = txtETitle.Text.Trim();
     myMail.Body = txtEContent.Text.Trim();
     if (cboxAccessories.Items.Count > 0)
     {
      for (int i = 0; i < cboxAccessories.Items.Count; i++)
      { //建立邮件附件类的一个对象，语法格式为System.Net.Mail.Attachment(文件名，文件格式)
       System.Net.Mail.Attachment myAttachment = new System.Net.Mail.Attachment(
       cboxAccessories.Items[i].ToString(), System.Net.Mime.MediaTypeNames.Application.Octet);
       //MIME协议下的一个对象，用以设置附件的创建时间，修改时间以及读取时间
       System.Net.Mime.ContentDisposition disposition = myAttachment.ContentDisposition;
       disposition.CreationDate = System.IO.File.GetCreationTime(file);
       disposition.ModificationDate = System.IO.File.GetLastWriteTime(file);
       disposition.ReadDate = System.IO.File.GetLastAccessTime(file);
       //用smtpclient对象里attachments属性，添加上面设置好的myattachment
       myMail.Attachments.Add(myAttachment);
      }
     }
     //建立发送对象client,验证邮件服务器，服务器端口，用户名，以及密码
     System.Net.Mail.SmtpClient client = new System.Net.Mail.SmtpClient(txtSService.Text.Trim(), Convert.ToInt32(txtServicePort.Text.Trim()));
     client.Credentials = new System.Net.NetworkCredential(txtUPwd.Text.Trim(), txtCEmail.Text.Trim());
     client.Send(myMail);
     MessageBox.Show("邮件发送成功！", "提示", MessageBoxButtons.OK, MessageBoxIcon.Information);
    }
    catch (Exception ex)
    {
     MessageBox.Show(ex.Message, "提示", MessageBoxButtons.OK, MessageBoxIcon.Information);
    }
   }
  private void 删除上传文件_Click(object sender, EventArgs e)
  {
   if (cboxAccessories.Text == "")
   {
    MessageBox.Show("没有附件可删！", "提示", MessageBoxButtons.OK, MessageBoxIcon.Information);
   }
   else
   {
    cboxAccessories.Items.Remove(cboxAccessories.Text.Trim());
   }
  }
  }
}