HttpWebRequest.GetResponse() 失败时如何获取错误信息

我正在启动 HttpWebRequest，然后检索它的响应。有时，我会收到 500（或至少 5##）错误，但没有描述。我可以控制两个端点，并希望接收端获得更多信息。例如，我想将异常消息从服务器传递到客户端。使用 HttpWebRequest 和 HttpWebResponse 可以吗？

Code:

try
{
    HttpWebRequest webRequest = HttpWebRequest.Create(URL) as HttpWebRequest;
    webRequest.Method = WebRequestMethods.Http.Get;
    webRequest.Credentials = new NetworkCredential(Username, Password);
    webRequest.ContentType = "application/x-www-form-urlencoded";
    using(HttpWebResponse response = webRequest.GetResponse() as HttpWebResponse)
    {
        if(response.StatusCode == HttpStatusCode.OK)
        {
            // Do stuff with response.GetResponseStream();
        }
    }
}
catch(Exception ex)
{
    ShowError(ex);
    // if the server returns a 500 error than the webRequest.GetResponse() method
    // throws an exception and all I get is "The remote server returned an error: (500)."
}

任何对此的帮助将不胜感激。

使用 HttpWebRequest 和 HttpWebResponse 可以吗？

您可以让 Web 服务器简单地捕获异常文本并将其写入响应正文中，然后将状态代码设置为 500。现在，客户端在遇到 500 错误时会抛出异常，但您可以读取响应流并获取异常的消息。

所以你可以抓住一个Web异常 http://msdn.microsoft.com/en-us/library/system.net.webexception.aspx如果从服务器返回非 200 状态代码并读取其正文，将会抛出以下异常：

catch (WebException ex)
{
    using (var stream = ex.Response.GetResponseStream())
    using (var reader = new StreamReader(stream))
    {
        Console.WriteLine(reader.ReadToEnd());
    }
}
catch (Exception ex)
{
    // Something more serious happened
    // like for example you don't have network access
    // we cannot talk about a server exception here as
    // the server probably was never reached
}