c# - HttpWebRequest 和原生 GZip 压缩

Question

当请求一个使用 Gzip 压缩的页面时，我遇到了很多以下错误:

System.IO.InvalidDataException: The CRC in GZip footer does not match the CRC calculated from the decompressed data

我正在使用 native GZipStream 进行解压缩，并且正在考虑解决这个问题。考虑到这一点，是否有解决这个或另一个 GZip 库(免费？)的变通办法，可以正确处理这个问题？

我正在验证 webResponse ContentEncoding 是 GZIP

5/11 更新一个简化的片段

//Caller
public void SOSampleGet(string url) 
{
    // Initialize the WebRequest.
    webRequest = (HttpWebRequest)WebRequest.Create(url);
    webRequest.Method = WebRequestMethods.Http.Get;
    webRequest.KeepAlive = true;
    webRequest.Accept = "text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8";
    webRequest.Headers.Add("Accept-Encoding", "gzip,deflate");
    webRequest.Referer = WebUtil.GetDomain(url);

    HttpWebResponse webResponse = (HttpWebResponse)webRequest.GetResponse();    

    using (Stream stream = GetStreamForResponse(webResponse, READTIMEOUT_CONST))
    {
        //use stream
    }
}

//Method
private static Stream GetStreamForResponse(HttpWebResponse webResponse, int readTimeOut)
{
    Stream stream;
    switch (webResponse.ContentEncoding.ToUpperInvariant())
    {
        case "GZIP":
            stream = new GZipStream(webResponse.GetResponseStream(), CompressionMode.Decompress);
            break;
        case "DEFLATE":
            stream = new DeflateStream(webResponse.GetResponseStream(), CompressionMode.Decompress);
            break;

        default:
            stream = webResponse.GetResponseStream();
            stream.ReadTimeout = readTimeOut;
            break;
        }    
    return stream;
}

Answer 1

自 .net 2 以来可用的 webrequest AutomaticDecompression 属性怎么样？只需添加:

webRequest.AutomaticDecompression = DecompressionMethods.GZip | DecompressionMethods.Deflate;

它还将 gzip、deflate 添加到接受编码 header 。

参见 http://msdn.microsoft.com/en-us/library/system.net.httpwebrequest.automaticdecompression.aspx