ASP.NET Web API如何将请求标头“排序”到标头集合中？

Question

I was trying to read the value of the Content-Type header in a custom delegating handler in ASP.NET Web API. When I queried the request.Headers collection, the header value wasn't in there. However, it was contained in request.Content.Headers . Other non-standard headers (such as Content-Test ) starting with Content- were available in request.Headers only; Content-Length , on the other hand, could only be found within request.Content.Headers , just like Content-Type .

Is it correct to assume that Web API is putting all known content headers into the request.Content.Headers collection while putting all other headers into request.Headers ?

Answer 1

That's how the HttpClient was designed in the first place. Requests and responses are separate from the actual content hence content related cookies go into the HttpContent.Headers rather than HttpRequestMessage.Headers . Keeping the content headers with the content is a good way of separating the concerns, on the other hand, getting to the content headers is a bit more cumbersome.