Ajax跨域访问代理类，支持GET和POST方法

支持GET和POST两种方式
使用方法:http://localhost:4817/AppContainer/HttpProxy.ashx?httpproxy_request_url=http://www.g.cn&httpproxy_chars_set=gbk

 1<%@ WebHandler Language="C#" Class="HttpProxy" %>
 2
 3using System;
 4using System.Web;
 5using System.Text;
 6
 7public class HttpProxy : IHttpHandler
 8{
 9
10    public void ProcessRequest(HttpContext context)
11    {
12        HttpRequest Request = context.Request;
13        HttpResponse Response = context.Response;
14        try
15        {
16            string method = Request.HttpMethod;
17            System.Collections.Specialized.NameValueCollection data = new System.Collections.Specialized.NameValueCollection();
18            if (method == "POST")
19            {
20                data.Add(Request.Form);
21            }
22            else
23            {
24                data.Add(Request.QueryString);
25            }
26            string request_url = data["httpproxy_request_url"];
27            string chars_set = data["httpproxy_chars_set"];
28            if (string.IsNullOrEmpty(chars_set))
29            {
30                chars_set = "gbk";
31            }
32            Response.ContentEncoding = System.Text.Encoding.GetEncoding(chars_set);
33            if (string.IsNullOrEmpty(request_url))
34            {
35                Response.Write("请求地址不能为空.");
36                Response.End();
37            }
38            else
39            {
40                data.Remove("httpproxy_request_url");
41                data.Remove("httpproxy_chars_set");
42                string postdata = HttpHelper.ToNameValueString(data);
43                string result = string.Empty;
44                if (method == "POST")
45                {
46                    result = HttpHelper.Post(request_url, postdata, chars_set);
47                }
48                else
49                {
50
51                    result = HttpHelper.Get(request_url, chars_set);
52                }
53                Response.Write(result);
54                Response.End();
55            }
56        }
57        catch (Exception ex)
58        {
59            Response.Write("请求发生错误:" + ex.ToString());
60            Response.End();
61        }
62    }
63
64    public bool IsReusable
65    {
66        get
67        {
68            return false;
69        }
70    }
71
72}

 1using System.Text;
 2using System.Net;
 3using System.IO;
 4using System.Collections.Specialized;
 5
 6
 7public class HttpHelper
 8{
 9    /**//// <summary>
10    /// 向指定地址发送POST请求
11    /// </summary>
12    /// <param name="getUrl">指定的网页地址</param>
13    /// <param name="postData">POST的数据（格式为：p1=v1&p1=v2）</param>
14    /// <param name="chars_set">可采用如UTF-8,GB2312,GBK等</param>
15    /// <returns>页面返回内容</returns>
16    public static string Post(string postUrl, string postData, string chars_set)
17    {
18        Encoding encoding = Encoding.GetEncoding(chars_set);
19        HttpWebRequest Request = (HttpWebRequest)WebRequest.Create(postUrl);
20        Request.Method = "POST";
21        Request.ContentType = "application/x-www-form-urlencoded";
22        Request.AllowAutoRedirect = true;
23        byte[] postdata = encoding.GetBytes(postData);
24        using (Stream newStream = Request.GetRequestStream())
25        {
26            newStream.Write(postdata, 0, postdata.Length);
27        }
28        using (HttpWebResponse response = (HttpWebResponse)Request.GetResponse())
29        {
30            using (Stream stream = response.GetResponseStream())
31            {
32                using (StreamReader reader = new StreamReader(stream, encoding, true))
33                {
34                    return reader.ReadToEnd();
35                }
36            }
37        }
38    }
39
40    /**//// <summary>
41    /// 想地址发送GET请求
42    /// </summary>
43    /// <param name="getUrl">地址(格式:http://host/page?p1=v1&p2=v2</param>
44    /// <param name="chars_set">可采用如UTF-8,GB2312,GBK等</param>
45    /// <returns>页面返回内容</returns>
46    public static string Get(string getUrl, string chars_set)
47    {
48        CookieContainer cookie = new CookieContainer();
49        HttpWebRequest myRequest = (HttpWebRequest)WebRequest.Create(getUrl);
50        myRequest.AllowAutoRedirect = true;
51        myRequest.CookieContainer = cookie;
52        using (HttpWebResponse myresponse = (HttpWebResponse)myRequest.GetResponse())
53        {
54            myresponse.Cookies = cookie.GetCookies(myRequest.RequestUri);
55            using (Stream mystream = myresponse.GetResponseStream())
56            {
57                using (StreamReader myreader = new StreamReader(mystream, System.Text.Encoding.GetEncoding(chars_set), true))
58                {
59                    return myreader.ReadToEnd();
60                }
61            }
62        }
63    }
64    /**//// <summary>
65    /// 生成NameValueCollection字符串
66    /// 字符串格式如下：p1=v1&p2=v2&p3=v3&p4=v4
67    /// </summary>
68    /// <param name="data"></param>
69    /// <returns>字符串格式如下：p1=v1&p2=v2&p3=v3&p4=v4</returns>
70    public static string ToNameValueString(NameValueCollection data)
71    {
72        StringBuilder sb = new StringBuilder();
73        for (int i = 0; i < data.Count; i++)
74        {
75            if (i != 0) sb.Append("&");
76            sb.Append(data.GetKey(i)).Append("=").Append(data[i]);
77        }
78        return sb.ToString();
79    }
80}
81