1         /// <summary>
 2         /// 执行HTTP GET请求。
 3         /// </summary>
 4         /// <param name="url">请求地址</param>
 5         /// <param name="parameters">请求参数</param>
 6         /// <returns>HTTP响应</returns>
 7         public static string DoGet(string url, IDictionary<string, string> parameters)
 8         {
 9             if (parameters != null && parameters.Count > 0)
10             {
11                 if (url.Contains("?"))
12                 {
13                     url = url + "&" + BuildPostData(parameters);
14                 }
15                 else
16                 {
17                     url = url + "?" + BuildPostData(parameters);
18                 }
19             }
20 
21             HttpWebRequest req = (HttpWebRequest)WebRequest.Create(url);
22             req.ServicePoint.Expect100Continue = false;
23             req.Method = "GET";
24             req.KeepAlive = true;
25             req.UserAgent = "Test";
26             req.ContentType = "application/x-www-form-urlencoded;charset=utf-8";
27 
28             HttpWebResponse rsp = null;
29             try
30             {
31                 rsp = (HttpWebResponse)req.GetResponse();
32             }
33             catch (WebException webEx)
34             {
35                 if (webEx.Status == WebExceptionStatus.Timeout)
36                 {
37                     rsp = null;
38                 }
39             }
40 
41             if (rsp != null)
42             {
43                 if (rsp.CharacterSet != null)
44                 {
45                     Encoding encoding = Encoding.GetEncoding(rsp.CharacterSet);
46                     return GetResponseAsString(rsp, encoding);
47                 }
48                 else
49                 {
50                     return string.Empty;
51                 }
52             }
53             else
54             {
55                 return string.Empty;
56             }
57         }

 1         /// <summary>
 2         /// 把响应流转换为文本。
 3         /// </summary>
 4         /// <param name="rsp">响应流对象</param>
 5         /// <param name="encoding">编码方式</param>
 6         /// <returns>响应文本</returns>
 7         private static string GetResponseAsString(HttpWebResponse rsp, Encoding encoding)
 8         {
 9             StringBuilder result = new StringBuilder();
10             Stream stream = null;
11             StreamReader reader = null;
12 
13             try
14             {
15 
16                 // 以字符流的方式读取HTTP响应
17                 stream = rsp.GetResponseStream();
18                 reader = new StreamReader(stream, encoding);
19 
20                 // 每次读取不大于256个字符，并写入字符串
21                 char[] buffer = new char[256];
22                 int readBytes = 0;
23                 while ((readBytes = reader.Read(buffer, 0, buffer.Length)) > 0)
24                 {
25                     result.Append(buffer, 0, readBytes);
26                 }
27             }
28             catch (WebException webEx)
29             {
30                 if (webEx.Status == WebExceptionStatus.Timeout)
31                 {
32                     result = new StringBuilder();
33                 }
34             }
35             finally
36             {
37                 // 释放资源
38                 if (reader != null) reader.Close();
39                 if (stream != null) stream.Close();
40                 if (rsp != null) rsp.Close();
41             }
42 
43             return result.ToString();
44         }