C#通过POST发送数据函数，类似asp中的xmlhttp

 1 //purl处理页面,str参数（如：username=admin&passwod=123456）
 2 
 3 //返回处理页面输出的内容
 4 
 5 //使用：string data = PostData("http://www.zhangxun.net/", "action=Fav&str=这个是好网站");
 6 
 7        public static string PostData(string purl,string str)
 8         {
 9             try
10             {
11                 byte[] data = System.Text.Encoding.GetEncoding("GB2312").GetBytes(str);
12                 // 准备请求 
13                 HttpWebRequest req = (HttpWebRequest)WebRequest.Create(purl);
14 
15                 //设置超时
16                 req.Timeout = 30000;
17                 req.Method = "Post";
18                 req.ContentType = "application/x-www-form-urlencoded";
19                 req.ContentLength = data.Length;
20                 Stream stream = req.GetRequestStream();
21                 // 发送数据 
22                 stream.Write(data, 0, data.Length);
23                 stream.Close();
24 
25                 HttpWebResponse rep = (HttpWebResponse)req.GetResponse();
26                 Stream receiveStream = rep.GetResponseStream();
27                 Encoding encode = System.Text.Encoding.GetEncoding("GB2312");
28                 // Pipes the stream to a higher level stream reader with the required encoding format. 
29                 StreamReader readStream = new StreamReader(receiveStream, encode);
30 
31                 Char[] read = new Char[256];
32                 int count = readStream.Read(read, 0, 256);
33                 StringBuilder sb = new StringBuilder("");
34                 while (count > 0)
35                 {
36                     String readstr = new String(read, 0, count);
37                     sb.Append(readstr);
38                     count = readStream.Read(read, 0, 256);
39                 }
40 
41                 rep.Close();
42                 readStream.Close();
43 
44                 return sb.ToString();
45 
46             }
47             catch (Exception ex)
48             {
49                 return "";
50                // ForumExceptions.Log(ex);
51             }
52         }
53 
54