使用代理服务器

using System;
using System.Drawing;
using System.Collections;
using System.ComponentModel;
using System.Windows.Forms;
using System.Data;
// 添加新的命名空间。
using System.Net;
using System.IO;

namespace Proxy
{
    /**//// <summary>
    /// 使用代理服务器。
    /// </summary>
    public class Form1 : System.Windows.Forms.Form
    {
        private System.Windows.Forms.Button button1;
        private System.Windows.Forms.Button button2;
        private System.Windows.Forms.RichTextBox richTextBox1;
        /**//// <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 );
        }

        Windows Form Designer generated code#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.button1 = new System.Windows.Forms.Button();
            this.button2 = new System.Windows.Forms.Button();
            this.richTextBox1 = new System.Windows.Forms.RichTextBox();
            this.SuspendLayout();
            //
            // button1
            //
            this.button1.Location = new System.Drawing.Point(120, 8);
            this.button1.Name = "button1";
            this.button1.Size = new System.Drawing.Size(56, 23);
            this.button1.TabIndex = 2;
            this.button1.Text = "默认";
            this.button1.TextAlign = System.Drawing.ContentAlignment.TopCenter;
            this.button1.Click += new System.EventHandler(this.button1_Click);
            //
            // button2
            //
            this.button2.Location = new System.Drawing.Point(232, 8);
            this.button2.Name = "button2";
            this.button2.Size = new System.Drawing.Size(56, 23);
            this.button2.TabIndex = 3;
            this.button2.Text = "专门";
            this.button2.TextAlign = System.Drawing.ContentAlignment.TopCenter;
            this.button2.Click += new System.EventHandler(this.button2_Click);
            //
            // richTextBox1
            //
            this.richTextBox1.Dock = System.Windows.Forms.DockStyle.Bottom;
            this.richTextBox1.Location = new System.Drawing.Point(0, 40);
            this.richTextBox1.Name = "richTextBox1";
            this.richTextBox1.ScrollBars = System.Windows.Forms.RichTextBoxScrollBars.ForcedBoth;
            this.richTextBox1.Size = new System.Drawing.Size(408, 256);
            this.richTextBox1.TabIndex = 4;
            this.richTextBox1.Text = "";
            this.richTextBox1.WordWrap = false;
            //
            // Form1
            //
            this.AutoScaleBaseSize = new System.Drawing.Size(8, 18);
            this.ClientSize = new System.Drawing.Size(408, 296);
            this.Controls.AddRange(new System.Windows.Forms.Control[] {
                                                                          this.richTextBox1,
                                                                          this.button2,
                                                                          this.button1});
            this.FormBorderStyle = System.Windows.Forms.FormBorderStyle.FixedDialog;
            this.MaximizeBox = false;
            this.Name = "Form1";
            this.StartPosition = System.Windows.Forms.FormStartPosition.CenterScreen;
            this.Text = "Proxy";
            this.ResumeLayout(false);

        }
        #endregion

        /**//// <summary>
        /// 应用程序的主入口点。
        /// </summary>
        [STAThread]
        static void Main()
        {
            Application.Run(new Form1());
        }
        // 定义私有变量。
        public HttpWebRequest req;
        public HttpWebResponse res;
        public WebProxy proxy;
        public Stream s;
        public StreamReader r;
        // 使用默认代理。
        private void button1_Click(object sender, System.EventArgs e)
        {
            button1.Enabled = false;
            proxy = new WebProxy("http://127.0.0.1:8888", true);
            GlobalProxySelection.Select = proxy;
            req = (HttpWebRequest)WebRequest.Create("http://www.microsoft.com");
            res = (HttpWebResponse)req.GetResponse();
            s = res.GetResponseStream();
            r = new StreamReader(s);
            richTextBox1.Text = r.ReadToEnd();
            r.Close();
            s.Close();
            res.Close();
            button1.Enabled = true;
        }
        // 使用专门代理。
        private void button2_Click(object sender, System.EventArgs e)
        {
            button2.Enabled = false;
            proxy = new WebProxy("http://127.0.0.1:8887", true);
            req = (HttpWebRequest)WebRequest.Create("http://www.microsoft.com");
            req.Proxy = proxy;
            res = (HttpWebResponse)req.GetResponse();
            s = res.GetResponseStream();
            r = new StreamReader(s);
            richTextBox1.Text = r.ReadToEnd();
            r.Close();
            s.Close();
            res.Close();
            button2.Enabled = true;
        }
    }
}