Jquery – How to make $.post() use contentType=application/json

ajaxcontent-typejquery

I've noticed that when using $.post() in jquery that the default contentType is application/x-www-form-urlencoded – when my asp.net mvc code needs to have contentType=application/json

(See this question for why I must use application/json: ASPNET MVC – Why is ModelState.IsValid false "The x field is required" when that field does have a value?)

How can I make $.post() send contentType=application/json? I already have a large number of $.post() functions, so I don't want to change to $.ajax() because it would take too much time

If I try

$.post(url, data, function(), "json")

It still has contentType=application/x-www-form-urlencoded. So what exactly does the "json" param do if it does not change the contenttype to json?

If I try

$.ajaxSetup({
  contentType: "application/json; charset=utf-8"
});

That works but affects every single $.get and $.post that I have and causes some to break.

So is there some way that I can change the behavior of $.post() to send contentType=application/json?

Best Answer

$.ajax({
  url:url,
  type:"POST",
  data:data,
  contentType:"application/json; charset=utf-8",
  dataType:"json",
  success: function(){
    ...
  }
})

See : jQuery.ajax()

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