如何在C＃.NET/Mono中使用HTTP库的请求响应

Question

现在我一直试图使用Launchpad's API来使用C＃.NET或Mono编写一个小封装器。 按照OAuth，我首先需要得到签署的请求和Launchpad has it's own way of doing so。

我需要做的是创建一个连接到https://edge.launchpad.net/+request-token与一些必要的HTTP头如Content-type。在python中我有urllib2，但当我浏览System.Net命名空间时，它吹掉了我的头。我无法理解如何从它开始。我是否可以使用WebRequest,HttpWebRequest或WebClient存在很多混淆。使用WebClient我甚至会得到证书错误，因为它们不是作为可信的添加的。

从API文档，它说，三个按键需要通过POST

• auth_consumer_key来发送：你的消费者的关键
• oauth_signature_method：字符串 “明文字母”
• oauth_signature：字符串 “&” 。

所以HTTP请求可能是这样的：

POST /+request-token HTTP/1.1 
Host: edge.launchpad.net 
Content-type: application/x-www-form-urlencoded 

oauth_consumer_key=just+testing&oauth_signature_method=PLAINTEXT&oauth_signature=%26 

的反应应该是这个样子：

200 OK 

oauth_token=9kDgVhXlcVn52HGgCWxq&oauth_token_secret=jMth55Zn3pbkPGNht450XHNcHVGTJm9Cqf5ww5HlfxfhEEPKFflMqCXHNVWnj2sWgdPjqDJNRDFlt92f 

我改变了我的代码很多次，终于我可以得到它像

HttpWebRequest clnt = HttpWebRequest.Create(baseAddress) as HttpWebRequest; 
// Set the content type 
clnt.ContentType = "application/x-www-form-urlencoded"; 
clnt.Method = "POST"; 

string[] listOfData ={ 
    "oauth_consumer_key="+oauth_consumer_key, 
    "oauth_signature="+oauth_signature, 
    "oauth_signature_method"+oauth_signature_method 
}; 

string postData = string.Join("&",listOfData); 
byte[] dataBytes= Encoding.ASCII.GetBytes(postData); 

Stream newStream = clnt.GetRequestStream(); 
newStream.Write(dataBytes,0,dataBytes.Length); 

我该如何进行furth呃？我应该在clnt上做一个阅读电话吗？

为什么.NET开发人员不能创建一个我们可以用来读写的类，而不是创建数百个类并混淆每个新手。

Answer 1

不，您需要在获取响应流之前关闭请求流。
事情是这样的：

Stream s= null; 
try 
{ 
    s = clnt.GetRequestStream(); 
    s.Write(dataBytes, 0, dataBytes.Length); 
    s.Close(); 

    // get the response 
    try 
    { 
     HttpWebResponse resp = (HttpWebResponse) req.GetResponse(); 
     if (resp == null) return null; 

     // expected response is a 200 
     if ((int)(resp.StatusCode) != 200) 
      throw new Exception(String.Format("unexpected status code ({0})", resp.StatusCode)); 
     for(int i=0; i < resp.Headers.Count; ++i) 
       ; //whatever 

     var MyStreamReader = new System.IO.StreamReader(resp.GetResponseStream()); 
     string fullResponse = MyStreamReader.ReadToEnd().Trim(); 
    } 
    catch (Exception ex1) 
    { 
     // handle 404, 503, etc...here 
    } 
}  
catch 
{ 
} 

但是，如果你并不需要所有的控制，可以更简单地做一个Web客户端请求。

string address = "https://edge.launchpad.net/+request-token"; 
string data = "oauth_consumer_key=just+testing&oauth_signature_method=...."; 
string reply = null; 
using (WebClient client = new WebClient()) 
{ 
    client.Headers.Add("Content-Type","application/x-www-form-urlencoded"); 
    reply = client.UploadString (address, data); 
} 

完整的工作代码（在.NET v3.5版本编译）：

using System; 
using System.Net; 
using System.Collections.Generic; 
using System.Reflection; 

// to allow fast ngen 
[assembly: AssemblyTitle("launchpad.cs")] 
[assembly: AssemblyDescription("insert purpose here")] 
[assembly: AssemblyConfiguration("")] 
[assembly: AssemblyCompany("Dino Chiesa")] 
[assembly: AssemblyProduct("Tools")] 
[assembly: AssemblyCopyright("Copyright © Dino Chiesa 2010")] 
[assembly: AssemblyTrademark("")] 
[assembly: AssemblyCulture("")] 
[assembly: AssemblyVersion("1.1.1.1")] 

namespace Cheeso.ToolsAndTests 
{ 
    public class launchpad 
    { 
     public void Run() 
     { 
      // see http://tinyurl.com/yfkhwkq 
      string address = "https://edge.launchpad.net/+request-token"; 

      string oauth_consumer_key = "stackoverflow1"; 
      string oauth_signature_method = "PLAINTEXT"; 
      string oauth_signature = "%26"; 

      string[] listOfData ={ 
       "oauth_consumer_key="+oauth_consumer_key, 
       "oauth_signature_method="+oauth_signature_method, 
       "oauth_signature="+oauth_signature 
      }; 

      string data = String.Join("&",listOfData); 

      string reply = null; 
      using (WebClient client = new WebClient()) 
      { 
       client.Headers.Add("Content-Type","application/x-www-form-urlencoded"); 
       reply = client.UploadString (address, data); 
      } 

      System.Console.WriteLine("response: {0}", reply); 
     } 

     public static void Usage() 
     { 
      Console.WriteLine("\nlaunchpad: request token from launchpad.net\n"); 
      Console.WriteLine("Usage:\n launchpad"); 
     } 


     public static void Main(string[] args) 
     { 
      try 
      { 
       new launchpad() 
        .Run(); 
      } 
      catch (System.Exception exc1) 
      { 
       Console.WriteLine("Exception: {0}", exc1.ToString()); 
       Usage(); 
      } 
     } 
    } 
}