C#HTTP代理的实现之注册表实现

HTTP代理的实现形式，可以通过修改注册表项，然后启动浏览器来实现，也可以通过SOCKET通信，构造HTTP头实现。下面是关于注册表实现的方式。

注册表实现，只需要修改几个关键的注册表项就可以了。

第一项：启用代理的注册表项。

第二项：代理的IP和端口。

第三项：连接的方式。

第四项：让注册表项立即生效。严格来说，这一步并没有修改注册表项，而是调用API通知注册表项生效。

下面是相关代码：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Runtime.InteropServices;
using System.Diagnostics;
using Microsoft.Win32;

namespace UtilSp.ClassLib
{
    public class ProxySp
    {
        [DllImport("wininet.dll", SetLastError = true)]
        private static extern bool InternetSetOption(IntPtr hInternet, int dwOption, IntPtr lpBuffer, int lpdwBufferLength);

        private const int INTERNET_OPTION_REFRESH = 37;
        private const int INTERNET_OPTION_PROXY = 38;
        private const int INTERNET_OPTION_SETTINGS_CHANGED = 39;
        private const int INTERNET_OPEN_TYPE_PROXY = 3;
        private const int INTERNET_OPEN_TYPE_DIRECT = 1;

        #region changeUserAgent Function
        public static void changeUserAgent()
        {
            var appName = Process.GetCurrentProcess().MainModule.ModuleName;
            RegeditSp.write(@"HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Internet Explorer\MAIN\FeatureControl\FEATURE_BROWSER_EMULATION", appName, 9999, RegistryValueKind.DWord);
        }
        #endregion

        #region setProxyEnabled Function
        /// <summary>
        /// Set proxy.
        /// </summary>
        /// <param name="isProxyEnabled">true:is enabled.false:is not enabled.</param>
        /// <param name="proxyIP">Proxy ip and port.Format:192.168.100.162:8080</param>
        /// <returns></returns>
        public static bool setProxy(bool isProxyEnabled, string proxyIP = "")
        {
            string regPath = "Software\\Microsoft\\Windows\\CurrentVersion\\Internet Settings";//Enabled proxy option.
            bool isSetProxyEnabledOk =
                RegeditSp.write(RegeditSp.REGEDIT_ROOT_SET.HKEY_CURRENT_USER,
                                regPath,
                                "ProxyEnable",
                                isProxyEnabled ? 1 : 0,
                                true);
            bool isSetProxyIP = true;
            if (!string.IsNullOrEmpty(proxyIP))
            {
                isSetProxyIP = RegeditSp.write(RegeditSp.REGEDIT_ROOT_SET.HKEY_CURRENT_USER,
                                                regPath,
                                                "ProxyServer",
                                                proxyIP,
                                                true);
            }
            bool isConnectionOK=setConnection(isProxyEnabled, proxyIP);
            bool isNotifyOk = InternetSetOption(IntPtr.Zero, INTERNET_OPTION_SETTINGS_CHANGED, IntPtr.Zero, 0);//Notify proxy in the regedit has changed.Lanuch proxy when connect next.
            bool isReadOK = InternetSetOption(IntPtr.Zero, INTERNET_OPTION_REFRESH, IntPtr.Zero, 0);//Read proxy from regedit.
            return isSetProxyEnabledOk && isSetProxyIP && isNotifyOk && isReadOK && isConnectionOK;
        }
        #endregion

        #region setConnection Function
        private static bool setConnection(bool isProxyEnabled, string proxyIP)
        {
            string regPath = "Software\\Microsoft\\Windows\\CurrentVersion\\Internet Settings\\Connections";//Connection register option.
            byte[] szBuf = new byte[80];
            szBuf[0] = 0x3c;
            szBuf[4] = 0x09;
            szBuf[8] = (byte)(isProxyEnabled ? 0x03 : 0x01);

            szBuf[12] = (byte)proxyIP.Length;
            for (int i = 0; i < proxyIP.Length; i++)
            {
                szBuf[i + 16] =(byte)Convert.ToInt32(proxyIP[i]);
            }
            string local = "<local>";
            for (int j = 0; j < 7; j++)
            {
                szBuf[20 + proxyIP.Length + j] = (byte)Convert.ToInt32(local[j]);
            }

            return  RegeditSp.write(RegeditSp.REGEDIT_ROOT_SET.HKEY_CURRENT_USER,
                                regPath,
                                "宽带连接",
                                szBuf,
                                true);
        }
        #endregion
    }
}

附上工程代码
http://download.csdn.net/detail/xxdddail/5831359。工程中实现了自动用代理IP列表刷网页的功能。