WebClient.DownloadData自动decode了uri

Question

相同代码代码在不同项目(console application,web form application)时，我用fiddler抓取http请求包
发现在web项目时请求的数据包被decode过了，而console项目不会这样且保持我传入的uri。

这是.net的bug吗？如果可以绕过这个decode？

public static string ReadFromUrl(string url)

{
    string content = "";
    WebResponse response = null;
    StreamReader streamReader = null;
    Stream receiveStream = null;
    try
    {
        WebRequest request = WebRequest.Create(url);

        response = request.GetResponse();
        receiveStream = response.GetResponseStream();
        streamReader = new StreamReader(receiveStream);
        content = streamReader.ReadToEnd();
    }
    catch (Exception ex)
    {
        Console.WriteLine(ex.Message);
    }
    finally
    {
        if (response != null)
        {
            response.Close();
        }
        streamReader.Close();
        receiveStream.Close();
    }
    return content;
}

请求url为：

http://objstore.qa.nt.ctripcorp.com/smartemailstorage/2017%5C4%5C6%5Cf809530b-0ded-49b4-8532-002c7ad73b41%5C%E9%98%BF%E9%87%8C%E5%B7%B4%E5%B7%B4Java%E5%BC%80%E5%8F%91%E6%89%8B%E5%86%8C.pdf?AWSAccessKeyId=D1NNJCXLEF0O7JIB2U3L&Expires=1511426288&Signature=iJjQCreO6F7avac86Tg2S4e4Miw%3D

这是个内部链接，应该是访问不了，不过可以用fiddler抓包来获取请求的地址