Cannot send a content-body with this verb-type

问题:

I just got this exception (ProtocolViolationException) in my .NET 2.0 app (running on windows mobile 6 standard emulator). What confuses me is that as far as i know, I have not added any content body, unless I've inadvertently done it somehow. My code is below (very simple). Is there anything else i need to do to convince .NET that this is just a http GET?

Thanks, brian

//run get and grab response
WebRequest request = WebRequest.Create(get.AbsoluteUri + args);
request.Method = "GET";
Stream stream = request.GetRequestStream();           // <= explodes here
XmlTextReader reader = new XmlTextReader(stream);

回答1:

Don't get the request stream, quite simply. GET requests don't usually have bodies (even though it's not technically prohibited by HTTP) and WebRequest doesn't support it - but that's what calling GetRequestStream is for, providing body data for the request.

Given that you're trying to read from the stream, it looks to me like you actually want to get the response and read the response stream from that:

WebRequest request = WebRequest.Create(get.AbsoluteUri + args);
request.Method = "GET";
using (WebResponse response = request.GetResponse())
{
    using (Stream stream = response.GetResponseStream())
    {
        XmlTextReader reader = new XmlTextReader(stream);
        ...
    }
}

回答2:

Because you didn't specify the Header.

I've added an extended example:

var request = (HttpWebRequest)WebRequest.Create(strServer + strURL.Split('&')[1].ToString());

Header(ref request, p_Method);

And the method Header:

private void Header(ref HttpWebRequest p_request, string p_Method)
{
    p_request.ContentType = "application/x-www-form-urlencoded";
    p_request.Method = p_Method;
    p_request.UserAgent = "Mozilla/4.0 (compatible; MSIE 6.0; Windows CE)";
    p_request.Host = strServer.Split('/')[2].ToString();
    p_request.Accept = "*/*";
    if (String.IsNullOrEmpty(strURLReferer))
    {
        p_request.Referer = strServer;
    }
    else
    {
        p_request.Referer = strURLReferer;
    }
    p_request.Headers.Add("Accept-Language", "en-us\r\n");
    p_request.Headers.Add("UA-CPU", "x86 \r\n");
    p_request.Headers.Add("Cache-Control", "no-cache\r\n");
    p_request.KeepAlive = true;
}

回答3:

I had the similar issue using Flurl.Http:

Flurl.Http.FlurlHttpException: Call failed. Cannot send a content-body with this verb-type. GET http://******:8301/api/v1/agents/**** ---> System.Net.ProtocolViolationException: Cannot send a content-body with this verb-type.

The problem was I used .WithHeader("Content-Type", "application/json") when creating IFlurlRequest.

回答4:

Please set the request Content Type before you read the response stream;

 request.ContentType = "text/xml";