Read Accept to determine the media types the Web client can accept in response to the request. Not every HTTP request message has an Accept header. If the Accept property is not set, then any media type is potentially acceptable in the response. 

Accept headers usually indicate that the response should be limited to a small set of desired types. For example, a Web client requesting an audio response might produce a TWebRequest object with Accept set to the following string:

audio/*; q=0.2, audio/basic

This request indicates that the preferred response media type is audio/basic, but that any audio type is acceptable if it is the best available after an 80% markdown in quality. 

For information on the format of Accept headers, see the current Internet standards documentation. 

ContentType 

Properties That Describe the Expected Response