Content Negotiation in Web API

Whenever you access ASP.NET Web API from your client side script (JavaScript / jQuery) by default the data is returned in JSON format. However, in certain cases you lay want to retrieve the data in XML format instead of JSON. On the server side, Web API determinses what data format to use for sending data to the client by doing what is known as Content Negotiation. Simply put, content negotiation is a process by which Web API inspects the incoming request and HTTP headers accompanying the request to figure out what response format(s) the client can understand. Based on this checking Web API sends the output.

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