C# 为什么我能'；是否无法通过WebClient阅读此下载页面的响应者？

这是我想分析的页面（它是iso-8859-1）：

因此，如果您查看源代码：

<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">

但它显示：

Content-Length: 22967 
Content-Type: text/html 
Date: Fri, 17 Jan 2014 14:24:17 GMT Expires: Fri, 17 Jan 2014 14:24:16 GMT 
Set-Cookie: Lang=1; expires=Fri, 16-Jan-2015 23:00:00 GMT; path=/,ASPSESSIONIDACCAQTTC=PGGNBKJAHLBBCMELCOMHMHJG; path=/ 
Server: Microsoft-IIS/6.0 
X-Powered-By: ASP.NET 
Cache-control: private 

内容类型是
text/html
。它已丢失iso-8859-1

为什么?？我怎样才能得到它呢？
如果你想得到字符集值（页面编码），你可以试试这个

Encoding encoding = null;
using (WebClient client = new WebClient())
{
    string html = client.DownloadString(websiteUrl);
    encoding = doc.DetectEncodingHtml(html);
}

Content-Length: 22967 
Content-Type: text/html 
Date: Fri, 17 Jan 2014 14:24:17 GMT Expires: Fri, 17 Jan 2014 14:24:16 GMT 
Set-Cookie: Lang=1; expires=Fri, 16-Jan-2015 23:00:00 GMT; path=/,ASPSESSIONIDACCAQTTC=PGGNBKJAHLBBCMELCOMHMHJG; path=/ 
Server: Microsoft-IIS/6.0 
X-Powered-By: ASP.NET 
Cache-control: private 

Encoding encoding = null;
using (WebClient client = new WebClient())
{
    string html = client.DownloadString(websiteUrl);
    encoding = doc.DetectEncodingHtml(html);
}