再谈HTTP Post XML数据

之前写过一篇HTTPPost的文章http://www.cnblogs.com/qidian10/archive/2011/06/20/2085341.html

这篇文章的代码其实是有点问题的：第一次提交数据会不通过，然后再试的话都是没有问题的，一直不解，直到今天在MSDN上发现了解决方案，贴出代码如下：

protected string HttpPostData(string URL, string strParm, int outTime)
 {
 StringBuilder str = new StringBuilder();
 try
 {
 HttpWebRequest WRequest;
 HttpWebResponse WResponse = null;
 HttpWebResponse response = null;
 //preAuth the request
 // You can add logic so that you only pre-authenticate the very first request.
 // You should not have to pre-authenticate each request.
 Uri uri = new Uri(URL);
 WRequest = (HttpWebRequest)HttpWebRequest.Create(uri);
 WRequest.Credentials = new NetworkCredential("wcadmin", "wcadmin");
 WRequest.PreAuthenticate = true;
 WRequest.UserAgent = "Upload PLM XML";
 WRequest.Method = "HEAD";
 WRequest.Timeout = outTime;
 WResponse = (HttpWebResponse)WRequest.GetResponse();
 WResponse.Close();
 // Make the real request.
 WRequest = (HttpWebRequest)HttpWebRequest.Create(URL);
 WRequest.Credentials = new NetworkCredential("wcadmin", "wcadmin");
 WRequest.PreAuthenticate = true;
 WRequest.UserAgent = "Upload PLM XML";
 WRequest.Method = "POST";
 WRequest.AllowWriteStreamBuffering = false;
 WRequest.Timeout = 10000;
 Byte[] postBytes = Encoding.UTF8.GetBytes(strParm);
 WRequest.ContentLength = postBytes.Length;
 Stream requestStream = WRequest.GetRequestStream();
 requestStream.Write(postBytes, 0, postBytes.Length);
 requestStream.Close();
 try
 {
 response = (HttpWebResponse)WRequest.GetResponse();
 }
 catch (WebException e)
 {
 response = (HttpWebResponse)e.Response;
 }
 Stream responseStream = response.GetResponseStream();
 StreamReader streamReader = new StreamReader(responseStream, Encoding.Default);
 while (streamReader.Peek() != -1)
 {
 str.Append(streamReader.ReadLine());
 }
 streamReader.Close();
 response.Close();
 WResponse.Close();
 }
 catch (Exception error)
 {
 str.AppendLine(error.Message);
 }
 return str.ToString();
 }

注意英文注释的那一段，通过这个方法即可成功提交数据，不会遇到莫名的400错误了。

如果上面还是遇到问题，请参考下面的代码

http://www.cnblogs.com/hyl8218/archive/2011/07/04/2097394.html

要在发送请求的时候添加HTTP Basic Authentication认证信息到请求中，有两种方法：

• 一是在请求头中添加Authorization：
  Authorization: "Basic 用户名和密码的base64加密字符串"
• 二是在url中添加用户名和密码：
  http://userName:password@api.minicloud.com.cn/statuses/friends_timeline.xml

下面来看下对于第一种在请求中添加Authorization头部的各种语言的实现代码。

先看.NET的吧：

string username="username";
string password="password";
//注意这里的格式哦，为 "username:password"
string usernamePassword = username + ":" + password;
CredentialCache mycache = new CredentialCache();
mycache.Add(new Uri(url), "Basic", new NetworkCredential(username, password));
myReq.Credentials = mycache;
myReq.Headers.Add("Authorization", "Basic " + Convert.ToBase64String(new ASCIIEncoding().GetBytes(usernamePassword))); 

WebResponse wr = myReq.GetResponse();
Stream receiveStream = wr.GetResponseStream();
StreamReader reader = new StreamReader(receiveStream, Encoding.UTF8);
string content = reader.ReadToEnd(); 

　　

你当然也可以使用HttpWebRequest或者其他的类来发送请求。