我的 HttpWebRequest 有什么问题

Question

我不知道我的代码中缺少什么。

如果我调用 404 url​​，我的代码会出现异常。

HttpWebRequest req = WebRequest.Create(args.Url) as HttpWebRequest;
req.AllowAutoRedirect = true;
req.Timeout = args.TimeOut;
req.UserAgent = args.UserAgent;   
HttpWebResponse answer = req.GetResponse() as HttpWebResponse;
objResult.Status =answer.StatusCode;
Stream stream = answer.GetResponseStream();

我在 req.GetResponse() 上遇到异常

有错误我回来了

远程服务器返回错误：(404) Not Found.

我不认为收到 HttpStatusCode.NotFound ？

解决办法：

try
      {
        HttpWebRequest req = WebRequest.Create(args.Url) as HttpWebRequest;
        req.AllowAutoRedirect = true;
        req.Timeout = args.TimeOut;
        req.UserAgent = args.UserAgent;       
        HttpWebResponse answer = req.GetResponse() as HttpWebResponse;

        objResult.Status =answer.StatusCode;       
      }
      catch (WebException ex)
      {
        HttpWebResponse response = ex.Response as HttpWebResponse;
        objResult.Status = response.StatusCode;       
      }

Answer 1

HttpWebRequest 在不成功的响应状态下引发异常。
此行为是设计使然。

您可以通过捕获WebException 并检查其Response 属性来获得响应。