How to get the input element triggering the jQuery autocomplete widget?

I was using an anonymous function for the source param, and $(this) inside it referenced the funcion, not the element that was triggering it. I had to use $(this.element).

The final code ended similar to this (I simplified it for demo purposes):

$( ".regionsAutocomplete" ).autocomplete({    source: function(request, response){        //The next line is the important one for this example        var input = this.element;        $(input).css('color','red');        var data = {'foo':'bar'};        $.ajax({            'url': ajaxurl,            'data': data,            'method': "POST",            'dataType': "json",            'success': function(data) {                response(data);            }        });    }});

Try using $(this)

$('input[type=text]').autocomplete({    source: 'suggestions.php',    select: function(event, ui) {        // here I need the input element that have triggered the event        alert($(this).attr('name'));    }});

You can use $(this) or event.target.

Then you can get the name using $(this).prop('name') or event.target.name.

demo