System.Net.HttpWebResponse.GetResponseStream()在WebException中返回截断的主体

时间:2011-02-07 04:41:03

标签: c# .net httpwebrequest system.net.webexception

由于某种原因,我理解对特定网站(https://learningnetwork.cisco.com/people/mrollins?view=profile)提出的请求会产生一个reqsponse对象,其响应流包含网站的主干版本。

流在65536字节之后结束,等于2 ^ 16字节。我认为这是一个可疑的数字。这些请求抱怨内部服务器错误,我对此表示赞同,因为我已经验证了webbrowsers能够理解这个响应,并且完整的html包含在服务器的响应中。 (使用fiddler

我发现之前记录的问题here,由于它在本说明中结束的简单原因而不能令人满意:

  

“我想我不得不希望这个错误   不超过65536个字符......“

好吧。

变通方法很受欢迎,或者如果有人知道一个好的修复程序也很好。

using System;
using System.IO;
using System.Net;
using System.Web.UI;

namespace Example
{
    public partial class _Default : Page
    {
        protected void Page_Load(object senderHidden, EventArgs eHidden)
        {
            //ServicePointManager.ServerCertificateValidationCallback += delegate(object sender, X509Certificate certificate, X509Chain chain, SslPolicyErrors sslPolicyErrors) { return true; };
            var cookieContainer = new CookieContainer();
            //Encoding enc = Encoding.UTF8;
            HttpWebRequest req = (HttpWebRequest)WebRequest.Create("https://learningnetwork.cisco.com/people/mrollins?view=profile");
            req.AllowAutoRedirect = false;

            req.AutomaticDecompression = DecompressionMethods.Deflate | DecompressionMethods.GZip;
            req.CookieContainer = cookieContainer;
            req.Accept = "text/xml,application/xml,application/xhtml+xml,text/html;q=0.9,text/plain;q=0.8,image/png,*/*;q=0.5";
            req.Method = "GET";
            req.UserAgent = "Mozilla/5.0 (Windows; U; Windows NT 5.1; ru; rv:1.8.1.12) Gecko/20080201 Firefox/2.0.0.12";
            req.KeepAlive = true;

            HttpWebResponse resp = null;
            try
            {
                resp = (HttpWebResponse)req.GetResponse();
            }
            catch (WebException e)
            {
                var r = e.Response as HttpWebResponse;
                var memstream = Read(r.GetResponseStream());
                var wrongLength = memstream.Length;
            }
        }

        public static MemoryStream Read(Stream stream)
        {
            MemoryStream memStream = new MemoryStream();

            byte[] readBuffer = new byte[4096];
            int bytesRead;
            while ((bytesRead = stream.Read(readBuffer, 0, readBuffer.Length)) > 0)
                memStream.Write(readBuffer, 0, bytesRead);
            return memStream;
        }
    }
}

1 个答案:

答案 0 :(得分:16)

HttpWebRequest有一个静态属性,可以限制Web请求的长度。在请求发出之前插入的这行代码解决了这个问题。

HttpWebRequest.DefaultMaximumErrorResponseLength = 1048576;