百度，google加自己理解后，将所得方法总结一下：
方法1：修改注册表Software//Microsoft//Windows//CurrentVersion//Internet Settings下 ProxyEnable和ProxyServer。这种方法适用于局域网用户，拨号用户无效。
1
public partial class Form1 : Form
2
{
3
4 //用于刷新注册表
5 [DllImport(@"wininet",
6 SetLastError = true,
7 CharSet = CharSet.Auto,
8 EntryPoint = "InternetSetOption",
9 CallingConvention = CallingConvention.StdCall)]
10
11
12 public static extern bool InternetSetOption
13 (
14 int hInternet,
15 int dmOption,
16 IntPtr lpBuffer,
17 int dwBufferLength
18 );
19
20 private void btnStart_Click(object sender, EventArgs e)
21
{
22 RegistryKey pregkey;
23 pregkey = Registry.CurrentUser.OpenSubKey("Software//Microsoft//Windows//CurrentVersion//Internet Settings", true);
24 if (pregkey == null)
25 {
26 Console.WriteLine("键值不存在");
27
}
28 else
29 {
30 pregkey.SetValue("ProxyEnable", 1);
31 pregkey.SetValue("ProxyServer", "代理地址");
32 //激活代理设置
33 InternetSetOption(0, 39, IntPtr.Zero, 0);
34 InternetSetOption(0, 37, IntPtr.Zero, 0);
35 webBrowser1.Navigate(txtweb.Text, false);
36 // System.Threading.Thread.Sleep(10000);
37 }
38 }
39
}
public partial class Form1 : Form2
{ 
3
4
//用于刷新注册表5
[DllImport(@"wininet",6
SetLastError = true,7
CharSet = CharSet.Auto,8
EntryPoint = "InternetSetOption",9
CallingConvention = CallingConvention.StdCall)]10
11
12
public static extern bool InternetSetOption13
(14
int hInternet,15
int dmOption,16
IntPtr lpBuffer,17
int dwBufferLength18
);19
20
private void btnStart_Click(object sender, EventArgs e)21
{
22
RegistryKey pregkey;23
pregkey = Registry.CurrentUser.OpenSubKey("Software//Microsoft//Windows//CurrentVersion//Internet Settings", true);24
if (pregkey == null)25
{26
Console.WriteLine("键值不存在");27
}28
else29
{30
pregkey.SetValue("ProxyEnable", 1);31
pregkey.SetValue("ProxyServer", "代理地址");32
//激活代理设置33
InternetSetOption(0, 39, IntPtr.Zero, 0);34
InternetSetOption(0, 37, IntPtr.Zero, 0);35
webBrowser1.Navigate(txtweb.Text, false);36
// System.Threading.Thread.Sleep(10000);37
}38
}39
}
方法2： 修改注册表 Software//Microsoft//Windows//CurrentVersion//Internet Settings//Connections下以你拨号连接名为键的值，该键为二进制。这种方法适用于拨号用户。
public partial class FrmMain : Form {[DllImport(@"wininet", SetLastError = true, CharSet = CharSet.Auto, EntryPoint = "InternetSetOption", CallingConvention = CallingConvention.StdCall)] public static extern bool InternetSetOption ( int hInternet, int dmOption, IntPtr lpBuffer, int dwBufferLength );//将值转换为注册表中的二进制值public byte ChangeTobyte(char i) { byte key = 0; switch (i) { case '0': key = 48; break; case '1': key = 49; break; case '2': key = 50; break; case '3': key = 51; break; case '4': key = 52; break; case '5': key = 53; break; case '6': key = 54; break; case '7': key = 55; break; case '8': key = 56; break; case '9': key = 57; break; case '.': key = 46; break; case ':': key = 58; break; } return key; }private void btnStart_Click(object sender, EventArgs e) { int i = ("代理地址").Length; byte[] key = new byte[50]; char[] source = ("代理地址").ToCharArray(); key[0] = 60; key[4] = 3; key[8] = 3; key[12] = (byte)i; for (int ii = 0; ii < source.Length; ii++) { key[16 + ii] = ChangeTobyte(source[ii]); } string sDirectX = ""; for (int k = 0; k < key.Length; k++) { if (key[k] != 0) { sDirectX += key[k] + " "; } } //MessageBox.Show(sDirectX); RegistryKey pregkey; pregkey = Registry.CurrentUser.OpenSubKey("Software//Microsoft//Windows//CurrentVersion//Internet Settings//Connections", true); if (pregkey == null) { Console.WriteLine("键值不存在"); } else { pregkey.SetValue("拨号名字对应键值", key, RegistryValueKind.Binary); //激活代理设置 InternetSetOption(0, 39, IntPtr.Zero, 0); InternetSetOption(0, 37, IntPtr.Zero, 0); webBrowser1.Navigate(txtweb.Text, false); webBrowser1.Refresh(); } }}
方法3： 使用c#自带的 webproxy类，使用这种方法可以获得目标网站的响应，但我不会把这种响应用IE反馈出来，有高手帮个忙么？
网上的代码说是MSDN的：
HttpWebRequest myWebRequest=(HttpWebRequest)WebRequest.Create(" http://www.microsoft.com"/);
WebProxy myProxy=new WebProxy();
// Obtain the 'Proxy' of the Default browser.
myProxy=(WebProxy)myWebRequest.Proxy; 这行我编译不通过
// Print the Proxy Url to the console.
Console.WriteLine("/nThe actual default Proxy settings are {0}",myProxy.Address);
try
{
Console.WriteLine("/nPlease enter the new Proxy Address that is to be set:");
Console.WriteLine("(Example: http://myproxy.example.com:port/)");
string proxyAddress;
proxyAddress =Console.ReadLine();
if(proxyAddress.Length>0)
{
Console.WriteLine("/nPlease enter the Credentials ");
Console.WriteLine("Username:");
string username;
username =Console.ReadLine();
Console.WriteLine("/nPassword:");
string password;
password =Console.ReadLine();
// Create a new Uri object.
Uri newUri=new Uri(proxyAddress);
// Associate the newUri object to 'myProxy' object so that new myProxy settings can be set.
myProxy.Address=newUri;
// Create a NetworkCredential object and associate it with the Proxy property of request object.
myProxy.Credentials=new NetworkCredential(username,password);
myWebRequest.Proxy=myProxy;
}
Console.WriteLine("/nThe Address of the new Proxy settings are {0}",myProxy.Address);
HttpWebResponse myWebResponse=(HttpWebResponse)myWebRequest.GetResponse();
我改了下：
HttpWebRequest myWebRequest = (HttpWebRequest)WebRequest.Create("http://www.123cha.com");
WebProxy myProxy = new WebProxy("代理地址", true);
try
{
Console.WriteLine("/nThe Address of the new Proxy settings are {0}", myProxy.Address);
HttpWebResponse myWebResponse = (HttpWebResponse)myWebRequest.GetResponse();
webBrowser1.DocumentStream = myWebResponse.GetResponseStream();
}
catch { }
