Question

我正在创建一个自定义WebClient类，其中包含WebClient框架类中没有的一些功能。我实际上像这样使用这个类：

using (var client = new CustomWebClient(10000))
{
     client.Tries = 5; //Number of tries that i want to get some page
     GetPage(client);
}

CustomWebClient类：

 public class CustomWebClient : WebClient
 {
    public CookieContainer Cookies { get; }
    public int Timeout { get; set; }
    public int Tries { get; set; }

    public CustomWebClient () : this(60000)
    {
    }

    public CustomWebClient (int timeOut)
    {
        Timeout = timeOut;
        Cookies = new CookieContainer();
        Encoding = Encoding.UTF8;
    }

    protected override WebRequest GetWebRequest(Uri address)
    {
       // some code here, but calling the base method
    }

    //this method actually is important to make the Tries logic.
    protected override WebResponse GetWebResponse(WebRequest request)
    {
        try
        {
            return base.GetWebResponse(request);
        }
        catch (WebException ex)
        {
            if(ex.Status == WebExceptionStatus.Timeout || ex.Status == WebExceptionStatus.ConnectFailure)
            if (--Tries == 0)
                throw;

            GetWebResponse(request);
        }
    }

   }

当10000毫秒结束时，我base.GetWebResponse(request);会WebException WebExceptionStatus.Timeout状态。减去了试验。但是当我执行GetWebResponse(request);重试获得响应时，它不会等待10000毫秒并再次抛出异常并继续直到5次尝试。如何再次获得响应，再提出请求？

感谢。

Answer 1

如评论中所述，您重复使用相同的WebRequest对象。您可以使用this answer中的代码克隆WebRequest对象，并将克隆传递给base.GetWebResponse（）类似这样的内容：

protected override WebResponse GetWebResponse(WebRequest request)
{
    WebRequest deepCopiedWebRequest = ObjectCopier.Clone<WebRequest>(request);
    try
    {
        return base.GetWebResponse(deepCopiedWebRequest);
    }
    catch (WebException ex)
    {
        if(ex.Status == WebExceptionStatus.Timeout || ex.Status == WebExceptionStatus.ConnectFailure)
        if (--Tries == 0)
            throw;

        GetWebResponse(request);
    }
}

如何重试获取超时异常的webclient请求

1 个答案: