Question

我试图从私人服务获取HTML页面内容。该页面返回状态代码0，该代码无效。但是在浏览浏览器时页面会进行渲染。

当我尝试使用WebResponse.GetResponseStream(）时，它只返回空流。当我尝试使用HttpClient.GetStringAsync(url)。结果时，它会抛出AggregateException，如下所示：

System.AggregateException was unhandled
  HResult=-2146233088
  Message=One or more errors occurred.
  Source=mscorlib
  StackTrace:
   at System.Threading.Tasks.Task.ThrowIfExceptional(Boolean includeTaskCanceledExceptions)
   at System.Threading.Tasks.Task`1.GetResultCore(Boolean waitCompletionNotification)
   at System.Threading.Tasks.Task`1.get_Result()
   at DiagnosticInfoCrawler.Program.Main(String[] args) in c:\TFS\MSNMetro\Tools\Verticals\Sports\DiagnosticInfoCrawler\Program.cs:line 47
   at System.AppDomain._nExecuteAssembly(RuntimeAssembly assembly, String[] args)
   at System.AppDomain.ExecuteAssembly(String assemblyFile, Evidence assemblySecurity, String[] args)
   at Microsoft.VisualStudio.HostingProcess.HostProc.RunUsersAssembly()
   at System.Threading.ThreadHelper.ThreadStart_Context(Object state)
   at System.Threading.ExecutionContext.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
   at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
   at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
   at System.Threading.ThreadHelper.ThreadStart()
  InnerException: System.Net.Http.HttpRequestException
   HResult=-2146233088
   Message=Response status code does not indicate success: 0 ().
   InnerException:

使用以下两种类型的代码：

WebResponse response = GetWebResponse(url);
responseBody = (new StreamReader(response.GetResponseStream())).ReadToEnd();

HttpClient httpClient = new HttpClient();
httpClient.BaseAddress = new Uri(url);
pageSource = httpClient.GetStringAsync(url).Result;

任何人都可以建议我如何获得回复机构？（鉴于我没有控制权来修复服务以返回正确的状态代码。）

谢谢你， DD

Answer 1

抓住WebException以获得回复。这是Microsoft的一个糟糕的设计决定，因为非200代码可以是正常情况的一部分。

try
{
    WebResponse response = GetWebResponse(url);
    responseBody = (new StreamReader(response.GetResponseStream())).ReadToEnd();

    HttpClient httpClient = new HttpClient();
    httpClient.BaseAddress = new Uri(url);
    pageSource = httpClient.GetStringAsync(url).Result;
}
catch (WebException exception)
{
    var response = (HttpWebResponse)exception.GetResponse();
    //the response is here..
}

Answer 2

没有直接解决这个问题，而是转向使用TcpClient来读取响应的方法。

当状态代码无效时如何获取http响应Body？

2 个答案: