jQuery: set 'selected' tag in options if value is in array

Question

I'm trying to add the selected attribute to the option tag using jQuery (on a Wordpress site). The values that should be selected are stored in a PHP array. Why does the selected attribute not get added to the <option>.. ?

my-script.js

jQuery("#location option").each(function($){

var arr = [<?php echo '"'.implode('","', $php_array).'"' ?>];
// for testing also hardcoded array: doesn't work either
// var arr = ["1", "2"];

   if(jQuery.inArray($(this).val(),arr) != -1){
     $(this).attr('selected', 'selected');
   };

});

The .js script is properly enqueqed.

html-output

   <select name="location[]" multiple="multiple" id="location" class="postform" style="display: none;">
            <option value="-1">Select a location</option>
            <option class="level-0" value="1">Location A</option>
            <option class="level-0" value="2">Location B</option>
            <option class="level-0" value="3">Location C</option>

        </select>

Answer 1

The problem is because you cannot pass anything to the each handler. Remove the $ from that and your code works fine:

var arr = ["1", "2"];
jQuery("#location option").each(function () {
    if (jQuery.inArray($(this).val(), arr) != -1) {
        $(this).prop('selected', true);
    };
});

Example Fiddle

Answer 2

I think you have typo in jQuery loop

jQuery("#location option").each(function($){

var arr = [<?php echo '"'.implode('","', $php_array).'"' ?>];
// for testing also hardcoded array: doesn't work either
// var arr = ["1", "2"];

   if(jQuery.inArray($(this).val(),arr) != -1){
     $(this).attr('selected', 'selected');
   };

});

function($) should be without parameter, like this function()

Working code:

jQuery("#location option").each(function(){

var arr = [<?php echo '"'.implode('","', $php_array).'"' ?>];
// for testing also hardcoded array: doesn't work either
// var arr = ["1", "2"];

   if(jQuery.inArray($(this).val(),arr) != -1){
     $(this).attr('selected', 'selected');
   };

});

my jsFiddle: http://jsfiddle.net/Cs329/