using System; 
 using System.Drawing; 
 using System.Collections; 
 using System.ComponentModel; 
 using System.Windows.Forms; 
 using System.Data; 
 using System.Web.Mail ; namespace 利用.Net类库发送电子邮件 
 { 
 /// <summary> 
 /// Form1 的摘要说明。 
 /// </summary> 
 public class Form1 : System.Windows.Forms.Form 
 { 
  private System.Windows.Forms.Label label3; 
  private System.Windows.Forms.Label label2; 
  private System.Windows.Forms.Label label1; 
  private System.Windows.Forms.OpenFileDialog openFileDialog1; 
  private System.Windows.Forms.Label label4; 
  private System.Windows.Forms.Button button2; 
  private System.Windows.Forms.Button button1; 
  private System.Windows.Forms.TextBox textBox4; 
  private System.Windows.Forms.TextBox textBox3; 
  private System.Windows.Forms.TextBox textBox2; 
  private System.Windows.Forms.TextBox textBox1; 
  private System.Windows.Forms.TextBox textBox5; 
  /// <summary> 
  /// 必需的设计器变量。 
  /// </summary> 
  private System.ComponentModel.Container components = null;  public Form1() 
  { 
   // 
   // Windows 窗体设计器支持所必需的 
   // 
   InitializeComponent();   // 
   // TODO: 在 InitializeComponent 调用后添加任何构造函数代码 
   // 
  }  /// <summary> 
  /// 清理所有正在使用的资源。 
  /// </summary> 
  protected override void Dispose( bool disposing ) 
  { 
   if( disposing ) 
   { 
   if (components != null) 
   { 
    components.Dispose(); 
   } 
   } 
   base.Dispose( disposing ); 
  }  #region Windows Form Designer generated code 
  /// <summary> 
  /// 设计器支持所需的方法 - 不要使用代码编辑器修改 
  /// 此方法的内容。 
  /// </summary> 
  private void InitializeComponent() 
  { 
   this.button2 = new System.Windows.Forms.Button(); 
   this.textBox4 = new System.Windows.Forms.TextBox(); 
   this.label4 = new System.Windows.Forms.Label(); 
   this.button1 = new System.Windows.Forms.Button(); 
   this.label3 = new System.Windows.Forms.Label(); 
   this.label2 = new System.Windows.Forms.Label(); 
   this.label1 = new System.Windows.Forms.Label(); 
   this.textBox3 = new System.Windows.Forms.TextBox(); 
   this.textBox2 = new System.Windows.Forms.TextBox(); 
   this.textBox1 = new System.Windows.Forms.TextBox(); 
   this.textBox5 = new System.Windows.Forms.TextBox(); 
   this.openFileDialog1 = new System.Windows.Forms.OpenFileDialog(); 
   this.SuspendLayout(); 
   // 
   // button2 
   // 
   this.button2.FlatStyle = System.Windows.Forms.FlatStyle.Flat; 
   this.button2.Location = new System.Drawing.Point(200, 114); 
    = "button2"; 
   this.button2.Size = new System.Drawing.Size(66, 28); 
   this.button2.TabIndex = 19; 
   this.button2.Text = "添加附件"; 
   this.button2.Click += new System.EventHandler(this.button2_Click); 
   // 
   // textBox4 
   // 
   this.textBox4.BorderStyle = System.Windows.Forms.BorderStyle.FixedSingle; 
   this.textBox4.Location = new System.Drawing.Point(72, 116); 
    = "textBox4"; 
   this.textBox4.Size = new System.Drawing.Size(122, 21); 
   this.textBox4.TabIndex = 17; 
   this.textBox4.Text = ""; 
   // 
   // label4 
   // 
   this.label4.Font = new System.Drawing.Font("宋体", 9F); 
   this.label4.Location = new System.Drawing.Point(18, 116); 
    = "label4"; 
   this.label4.Size = new System.Drawing.Size(62, 18); 
   this.label4.TabIndex = 20; 
   this.label4.Text = "附 件:"; 
   // 
   // button1 
   // 
   this.button1.FlatStyle = System.Windows.Forms.FlatStyle.Flat; 
   this.button1.Location = new System.Drawing.Point(106, 286); 
    = "button1"; 
   this.button1.Size = new System.Drawing.Size(92, 27); 
   this.button1.TabIndex = 21; 
   this.button1.Text = "发送邮件"; 
   this.button1.Click += new System.EventHandler(this.SendButton_Click); 
   // 
   // label3 
   // 
   this.label3.Font = new System.Drawing.Font("宋体", 9F); 
   this.label3.Location = new System.Drawing.Point(18, 84); 
    = "label3"; 
   this.label3.Size = new System.Drawing.Size(62, 18); 
   this.label3.TabIndex = 22; 
   this.label3.Text = "主 题:"; 
   // 
   // label2 
   // 
   this.label2.Font = new System.Drawing.Font("宋体", 9F); 
   this.label2.Location = new System.Drawing.Point(18, 52); 
    = "label2"; 
   this.label2.Size = new System.Drawing.Size(62, 18); 
   this.label2.TabIndex = 23; 
   this.label2.Text = "收信人:"; 
   // 
   // label1 
   // 
   this.label1.Font = new System.Drawing.Font("宋体", 9F); 
   this.label1.Location = new System.Drawing.Point(18, 22); 
    = "label1"; 
   this.label1.Size = new System.Drawing.Size(62, 18); 
   this.label1.TabIndex = 24; 
   this.label1.Text = "发信人:"; 
   // 
   // textBox3 
   // 
   this.textBox3.BorderStyle = System.Windows.Forms.BorderStyle.FixedSingle; 
   this.textBox3.Location = new System.Drawing.Point(72, 82); 
    = "textBox3"; 
   this.textBox3.Size = new System.Drawing.Size(174, 21); 
   this.textBox3.TabIndex = 16; 
   this.textBox3.Text = ""; 
   // 
   // textBox2 
   // 
   this.textBox2.BorderStyle = System.Windows.Forms.BorderStyle.FixedSingle; 
   this.textBox2.Location = new System.Drawing.Point(72, 48); 
    = "textBox2"; 
   this.textBox2.Size = new System.Drawing.Size(174, 21); 
   this.textBox2.TabIndex = 15; 
   this.textBox2.Text = ""; 
   // 
   // textBox1 
   // 
   this.textBox1.BorderStyle = System.Windows.Forms.BorderStyle.FixedSingle; 
   this.textBox1.Location = new System.Drawing.Point(72, 14); 
    = "textBox1"; 
   this.textBox1.Size = new System.Drawing.Size(174, 21); 
   this.textBox1.TabIndex = 14; 
   this.textBox1.Text = ""; 
   // 
   // textBox5 
   // 
   this.textBox5.BorderStyle = System.Windows.Forms.BorderStyle.FixedSingle; 
   this.textBox5.Location = new System.Drawing.Point(10, 154); 
   this.textBox5.Multiline = true; 
    = "textBox5"; 
   this.textBox5.Size = new System.Drawing.Size(276, 108); 
   this.textBox5.TabIndex = 18; 
   this.textBox5.Text = ""; 
   // 
   // openFileDialog1 
   // 
   this.openFileDialog1.Title = "选择附件:"; 
   // 
   // Form1 
   // 
   this.AutoScaleBaseSize = new System.Drawing.Size(6, 14); 
   this.ClientSize = new System.Drawing.Size(300, 335); 
   this.Controls.AddRange(new System.Windows.Forms.Control[] { 
           this.button2, 
           this.textBox4, 
           this.button1, 
           this.textBox3, 
           this.textBox2, 
           this.textBox1, 
           this.textBox5, 
           this.label4, 
           this.label3, 
           this.label2, 
           this.label1}); 
   this.FormBorderStyle = System.Windows.Forms.FormBorderStyle.FixedSingle; 
   this.MaximizeBox = false; 
    = "Form1"; 
   this.Text = "利用.Net类库发送电子邮件"; 
   this.ResumeLayout(false);  } 
  #endregion  /// <summary> 
  /// 应用程序的主入口点。 
  /// </summary> 
  [STAThread] 
  static void Main() 
  { 
   Application.Run(new Form1()); 
  }  private void SendButton_Click(object sender, System.EventArgs e) 
  { 
   try 
   { 
   MailMessage Message = new MailMessage ( ) ; 
   //新建一个MailMessage对象 
   Message.From = textBox1.Text ; 
   //定义发信人地址 
   Message.To = textBox2.Text ; 
   //定义收信人地址,如果是多人,可以用“,”分开 
   Message.Subject = textBox3.Text ; 
   //定义邮件的主题 
   Message.Body = textBox4.Text ; 
   //定义邮件的内容 
   if ( openFileDialog1.FileName != "" ) 
   { 
    MailAttachment Attachment = new MailAttachment ( openFileDialog1.FileName ,MailEncoding.Base64 ) ; 
    //以Base64编码创建一个附件实例 
    Message.Attachments.Add ( Attachment ) ; 
    //给邮件增加附件 
   } 
   //判断要发送的邮件是否有附件,如果有则加入 
   SmtpMail.Send ( Message ) ; 
   //发送电子邮件 
   MessageBox.Show( "电子邮件已经发送到->" + textBox2.Text ) ; 
   } 
   catch ( Exception ex ) 
   { 
   MessageBox.Show ( ex.Message.ToString ( ) ) ; 
   } 
  }  private void button2_Click ( object sender , System.EventArgs e ) 
  { 
   openFileDialog1.ShowDialog ( ) ; 
   //显示附件选择对话框 
   textBox4.Text = openFileDialog1.FileName ; 
  } 
 } 
 }