防止jQuery.ajax（）自动发送

Question

I need to do some (potentially asynchronous) stuff before sending an AJAX-request via jQuery. Is there any way to evoke the sending of the request on a jqXHR object manually? The problem is that I need to immediately return the jqXHR object (eg to use the $.Deferred() interface)

Answer 1

you can use beforeSend event in jQuery

 $.ajax({
      url: "url",
      beforeSend: function ( xhr ) {
      // you can do here 
      }
    }).done(function ( data ) {
     .............
    });

see here