AutoComplete in jQuery with dynamically added elements

My requirement is to show few options when user input some characters (minimum 3) in one of input field which might be added dynamically too.

I can not load data at page loading at beginning because data is huge. There is an ajax call to get that filtered data.

The issue what I am getting is Expected identifier error on page loading at line# 2. So, could you please tell what is wrong with the below code?

$(document).on('keydown.autocomplete', 'input.searchInput', function() {                
            source: function (request, response) { // Line # 2
            var id = this.element[0].id;

            var val = $("#"+id).val();             
            $.ajax({                     
                    type : 'Get',
                    url: 'getNames.html?name=' + val,
                    success: function(data) {
                        var id = $(this).attr('id');
                        $(this).removeClass('ui-autocomplete-loading'); 
                        response(data);
                    },error: function(data) {
                          $('#'+id).removeClass('ui-autocomplete-loading');  
                    }
                  });
              },
                minLength: 3
            });

Solution 1:

How about using another approach: initialize the autocomplete when you create the input:

$(function() {

  // settings for each autocomplete
  var autocompleteOptions = {
    minLength: 3,
    source: function(request, response) {
      $.ajax({
        type: "GET",
        url: "getNames.html",
        data: { name: request.term },
        success: function(data) {
          response(data);
        }
      });
    }
  };

  // dynamically create an input and initialize autocomplete on it
  function addInput() {
    var $input = $("<input>", {
      name: "search",
      "class": "searchInput",
      maxlength: "20"
    });
    $input
      .appendTo("form#myForm")
      .focus()
      .autocomplete(autocompleteOptions);
  };

  // initialize autocomplete on first input
  $("input.searchInput").autocomplete(autocompleteOptions);
  $("input#addButton").click(addInput);
});

<form id="myForm" name="myForm" method="post">
  <input id="addButton" type="button" value="Add an input" />
  <input name="search" class="searchInput" maxlength="20" />
</form>

jsFiddle with AJAX