ajaxSetup instantiated contentType not included when no data is sent

[briana@…]

Perhaps this was done purposely, but this is a change to the method.

 http://jsfiddle.net/kdgVJ/1/

[jitter]

I think this is only a little wording problem in the documentation. The  jQuery.ajax() documentation says:

contentType: [...] If you explicitly pass in a content-type to $.ajax() then it'll always be sent to the server (even if no data is sent).

These two test cases show that the documentation has to be taken literal.

 test case works as expected because contentType is passed directly to jQuery.ajax(...)

This  test case doesn't send the content-type header when there is no data as the contentType setting wasn't passed "directly" to jQuery.ajax(...)

So the documentation needs to be taken literal. Only if you pass the contentType option directly to $.ajax(...) it gets send even when there is no data.

[briana@…]

This is the specific case where I'm having an issue. Maybe this is just an issue with $.post():

 http://jsfiddle.net/G8zgB/

jQuery 1.4.3-1.4.4 will apply the contentType, other versions do not (so maybe this was never meant to happen?)

[danheberden]

Correct - this behaviour was actually a bug in 1.4.2/3. The method to force content-type as jitter explains is the only way.