在用HttpWebRequest对象时，一般我们都没有开启gzip压缩，如果服务端返回的数据比较大，这是我们需要开启gzip压缩，怎么开启呢？
1.给HttpWebRequest对象，添加如下Header：
request.Headers.Add("Accept-Encoding", "gzip");
2.对接收到的流进行解码：
private string GetResponseBody(HttpWebResponse response)
{
string responseBody = string.Empty;
if (response.ContentEncoding.ToLower().Contains("gzip")) {
using (GZipStream stream = new GZipStream(
response.GetResponseStream(), CompressionMode.Decompress))
{
using (StreamReaderreader = new StreamReader(stream))
{
responseBody = reader.ReadToEnd();
}
}
}
else if (response.ContentEncoding.ToLower().Contains("deflate"))
{
using (DeflateStream stream = new DeflateStream(
response.GetResponseStream(), CompressionMode.Decompress))
{
using (StreamReader reader =
new StreamReader(stream, Encoding.UTF8))
{
responseBody = reader.ReadToEnd();
}
}
}
else
{
using (Stream stream = response.GetResponseStream())
{
using (StreamReader reader =
new StreamReader(stream, Encoding.UTF8))
{
responseBody = reader.ReadToEnd();
}
}
}
return responseBody;
}
GZIP 头解析
原文：http://www.cnblogs.com/upshania/p/5521798.html
