HttpWebRequest返回503错误浏览器却能正常访问是什么原因？？

[weimeiangle1]

HttpWebRequest MyHttpWebRequest = (HttpWebRequest)WebRequest.Create("http://www.amazon.com/gp/offer-listing/B004PLY1EG");
MyHttpWebRequest.Timeout = 1000 * 60 * 10 * 10;
httpWebResponse = (HttpWebResponse)MyHttpWebRequest.GetResponse();
求解。

[孟子E章]

503状态码的含义是“Service Unavailable”，即临时不可访问(或许服务器不稳定、网站关闭等原因造成的)。

你可以改成这样

HttpWebRequest MyHttpWebRequest = (HttpWebRequest)WebRequest.Create("http://www.amazon.com/gp/offer-listing/B004PLY1EG");
MyHttpWebRequest.Timeout = 1000 * 60 * 10 * 10;
MyHttpWebRequest.Proxy = null;
MyHttpWebRequest.Method = "GET";
MyHttpWebRequest.Accept="text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8";
MyHttpWebRequest.Headers.Add("Accept-Language", "zh-cn,zh;q=0.8,en-us;q=0.5,en;q=0.3");
MyHttpWebRequest.UserAgent = "Mozilla/5.0 (Windows NT 5.2; rv:12.0) Gecko/20100101 Firefox/12.0";
HttpWebResponse httpWebResponse = (HttpWebResponse)MyHttpWebRequest.GetResponse();

[bdmh]

用抓包工具，看看浏览器访问网站时，都有哪些参数，然后按照 1 楼的方法，把参数写到对应的属性中

[weimeiangle1]

上述方法还是不行 也会返回503错误 有谁知道.如何用c#调用ie或firefox浏览器获得网页内容吗？

[ParanoidKing]

可以的。比如用Win7下简体中文IE8访问网站，用Fiddler抓下请求的信息，在http头里面会看到下面的数据：
Accept: */*
Accept-Encoding: gzip, deflate
Accept-Language: zh-CN
User-Agent: Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 6.1; Trident/4.0; SLCC2; .NET CLR 2.0.50727; .NET CLR 3.5.30729; .NET CLR 3.0.30729; Media Center PC 6.0; .NET4.0C; .NET4.0E)
然后照单填进HttpRequest里就行了：

MyHttpWebRequest.Accept = "*/*";
MyHttpWebRequest.Headers.Add(HttpRequestHeader.AcceptEncoding, "gzip, deflate");
MyHttpWebRequest.Headers.Add(HttpRequestHeader.AcceptLanguage, "zh-CN");
MyHttpWebRequest.UserAgent = "Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 6.1; Trident/4.0; SLCC2; .NET CLR 2.0.50727; .NET CLR 3.5.30729; .NET CLR 3.0.30729; Media Center PC 6.0; .NET4.0C; .NET4.0E)";

另外WinForm里有一个WebBrowse控件可以获取网页内容：

WebBrowser webBrowser = new WebBrowser();
Uri url = new Uri("http://www.amazon.com/gp/offer-listing/B004PLY1EG");
webBrowser.Url = url;
webBrowser.DocumentCompleted += new WebBrowserDocumentCompletedEventHandler((sender, e) => 
{
    if (e.Url == url)
    {
       string content = ((WebBrowser)sender).DocumentText;
    }
});