AJAX

The ajax() method is general method to perform an asynchronous HTTP request. Other methods are shorthand of ajax() method.

Except load(), methods return the jqXHR object.

$.get( "ajax/test.html", function(data) {
  $(".result").html(data);
  alert( "Load was performed." );
});

// load content of ajax/test.html into #result element
$( "#result" ).load( "ajax/test.html" );

// out: width=1680&height=1050
console.log($.param({ width:1680, height:1050 }));

// out something like: 
// single=Single&multiple=Multiple&multiple=Multiple3&check=check2&radio=radio1
$("form").on("submit", function(event) {
  event.preventDefault();
  console.log($(this).serialize());
});
more examples

callbacks

There are several ways to assign a request callbacks using.

• jqXHR object
• request settings
• global ajax event handlers

$.ajax("example.php", { // callbacks in request settings
  success: function(response) {
         alert( "success" );
    }
  statusCode: {
    404: function() {
      alert( "page not found" );
    }
  }
}).always(function() { // assign callback in jqXHR object
    alert( "complete" );
  });

Below ajax callback specifications.

request settings

Ajax settings are represented as a PlainObject type object. Most usefull fields are listed below.

$.ajax({
  url: "test.html",
  context: document.body
}).done(function() {
  $( this ).addClass( "done" );
});

jqXHR

The ajax methods return jqXHR object - the instance of jQuery XMLHttpRequest class. It wraps the browser's native XMLHttpRequest object and implements Promise interface.

Below some extra methods of jqXHR.