.addClass（）在for（）jQuery中不起作用

Question

UPDATE - FINAL SOLUTION

Thank you to EVERYONE who has helped me with this problem. Special thanks must go to @Pranav for all of their help through email . All of your answers seemed to have worked in JSFiddle yet I could not replicate it on my local server.

My problem was that my js file was firing before PHP had finished adding elements and classes dynamically. I was able to fix this (without using an event handler) with calling:

( function() {
    jQuery(window).load( function($) {

// Add stuff

});
})(jQuery);

This seems to wait until PHP has done its thang and then fire. I can see the changes happen in the DevTools panel.

I also didn't realise that Wordpress really doesn't seem to like $ and would rather have jQuery, so had to create $ = jQuery variable to counter this.

Once again, thank you all. I have only just started learning jQuery and Javascript and this has been a great lesson to learn.

---

ORIGINAL QUESTION

I am trying to add classes to a select boxes options depending on the classes they have been given by WooCommerce. (The reason for this is that I gave up trying to point to the 'disabled' property I couldn't get working.)

For some reason, the code I am using isn't adding any classes.

 jQuery(document).ready( function($) { // Classes for the link and the visible dropdown $selectclass='turnintodropdown'; // class to identify selects $listclass='turnintoselect'; // class to identify ULs $boxclass='dropcontainer'; // parent element $triggeron='activetrigger'; // class for the active trigger link $triggeroff='trigger'; // class for the inactive trigger link $dropdownclosed='dropdownhidden'; // closed dropdown $dropdownopen='dropdownvisible'; // open dropdown $i=0; $count=0; $sels=$('select'); $opts=$('option'); $trigger=('<a href="#"></a>'); function $switchTriggerClass (){ $($trigger).toggleClass($triggeron).toggleClass($triggeroff); } for($i; $i<$opts.length; $i++){ if($($opts).hasClass('enabled')){ $(this).addClass('woo'); } else { $(this).addClass('foo'); } } }); 

 <script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script> <tbody> <tr> <td class="label"> <label for="size">Size</label> </td> <td class="value"> <select id="size" class="turnintodropdown" name="attribute_size" data-attribute_name="attribute_size" data-show_option_none="yes"> <option value="">- -</option> <option value="10" class="attached enabled">10</option> <option value="20" class="attached enabled">20</option> <option value="30" class="attached enabled">30</option> <option value="40" class="attached enabled">40</option> <option value="50" class="attached" disabled="">50</option> <option value="60" class="attached" disabled="">60</option> </select> <a class="reset_variations" href="#" style="visibility: hidden;"></a> </td> </tr> </tbody> 

Any help would be greatly appreciated.

Regards Michael

EDIT Hi all,

I have tried all of these methods and the result is 'foo' being outputted to all option elements. I have also tried these methods on my navigation menu and the li elements are responding how I would expect this code to run.

My only conclusion has to be that Javascript/jQuery is not seeing the class 'enabled' even though it is definitely attached.

Could it be that the script is running before PHP has completed it processing? This is a dynamically loaded select box.

Cheers

Answer 1

Inside for loop this not refers to the element it may be window object or something else. Yo can resolve the problem using eq() method.

for(; $i < $opts.length; $i++){
    // cache the element reference
    var $item = $opts.eq($i);
    // or $($opts[$i])

    if($item .hasClass('enabled')){
        $item .addClass('woo');
    }
    else {
        $item .addClass('foo');
    }
}

 var $opts = $('option'); for (var $i = 0; $i < $opts.length; $i++) { // cache the element reference var $item = $opts.eq($i); // or $($opts[$i]) if ($item.hasClass('enabled')) { $item.addClass('woo'); } else { $item.addClass('foo'); } } 

 .foo { color: red } .woo { color: green; } 

 <script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script> <select id="size" class="turnintodropdown" name="attribute_size" data-attribute_name="attribute_size" data-show_option_none="yes"> <option value="">- -</option> <option value="10" class="attached enabled">10</option> <option value="20" class="attached enabled">20</option> <option value="30" class="attached enabled">30</option> <option value="40" class="attached enabled">40</option> <option value="50" class="attached" disabled="">50</option> <option value="60" class="attached" disabled="">60</option> </select> 

Or using each() method instead of for loop

$opts.each(function(){
    // cache the element reference
    $item = $(this);

    if($item .hasClass('enabled')){
        $item .addClass('woo');
    }
    else {
        $item .addClass('foo');
    }
});

 var $opts = $('option'); $opts.each(function() { // cache the element reference $item = $(this); if ($item.hasClass('enabled')) { $item.addClass('woo'); } else { $item.addClass('foo'); } }); 

 .foo { color: red } .woo { color: green; } 

 <script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script> <select id="size" class="turnintodropdown" name="attribute_size" data-attribute_name="attribute_size" data-show_option_none="yes"> <option value="">- -</option> <option value="10" class="attached enabled">10</option> <option value="20" class="attached enabled">20</option> <option value="30" class="attached enabled">30</option> <option value="40" class="attached enabled">40</option> <option value="50" class="attached" disabled="">50</option> <option value="60" class="attached" disabled="">60</option> </select> 

---

Even you can do it in 2 lines using filter() and not() methods.

// filter all elements with the class and add the class
$opts.filter('.enabled').addClass('woo');      

// filter all elements which doesn't have the class and add the class
$opts.not('.enabled').addClass('foo');

 var $opts = $('option'); // filter all elements with the class and add the class $opts.filter('.enabled').addClass('woo'); // filter all elements which doesn't have the class and add the class $opts.not('.enabled').addClass('foo'); 

 .foo { color: red } .woo { color: green; } 

 <script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script> <select id="size" class="turnintodropdown" name="attribute_size" data-attribute_name="attribute_size" data-show_option_none="yes"> <option value="">- -</option> <option value="10" class="attached enabled">10</option> <option value="20" class="attached enabled">20</option> <option value="30" class="attached enabled">30</option> <option value="40" class="attached enabled">40</option> <option value="50" class="attached" disabled="">50</option> <option value="60" class="attached" disabled="">60</option> </select> 

The same with a single line using end() method.

$opts
   .filter('.enabled').addClass('woo')
   // back to the previous element object
   .end()
   .not('.enabled').addClass('foo');

 var $opts = $('option'); // filter all elements with the class and add the class $opts.filter('.enabled').addClass('woo') .end() .not('.enabled').addClass('foo'); 

 .foo { color: red } .woo { color: green; } 

 <script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script> <select id="size" class="turnintodropdown" name="attribute_size" data-attribute_name="attribute_size" data-show_option_none="yes"> <option value="">- -</option> <option value="10" class="attached enabled">10</option> <option value="20" class="attached enabled">20</option> <option value="30" class="attached enabled">30</option> <option value="40" class="attached enabled">40</option> <option value="50" class="attached" disabled="">50</option> <option value="60" class="attached" disabled="">60</option> </select> 

Answer 2

You have to change your code block from

for($i; $i<$opts.length; $i++){
        if($($opts).hasClass('enabled')){
            $(this).addClass('woo');
        }
        else {
            $(this).addClass('foo');
        }
    }

To

$opts.each(function(){
    if($(this).hasClass('enabled'))
    {
        $(this).addClass('woo');
    }
    else
    {
        $(this).addClass('foo');
    }
})

---

Another way of doing is :

$('option.enabled').addClass('woo');      
$opts.not('.enabled').addClass('foo');

Answer 3

If you need an alternative then you can use foreach

$opts.each(function(){
        if(($(this)).hasClass('enabled')){
            $(this).addClass('woo');
        }
        else {
            $(this).addClass('foo');
        }
    })

Answer 4

Try this approach instead.

$sels.find('option').each(function() {
 if($(this).hasClass('enabled')) {
  $(this).addClass('woo');
 } else {
  $(this).addClass('foo');
 }
});

Answer 5

In side for loop this doesn't give you the current element in loop. you need to use $($opt[$i]).hasClass() inorder to access your options in select box.

 jQuery(document).ready( function($) { // Classes for the link and the visible dropdown $selectclass='turnintodropdown'; // class to identify selects $listclass='turnintoselect'; // class to identify ULs $boxclass='dropcontainer'; // parent element $triggeron='activetrigger'; // class for the active trigger link $triggeroff='trigger'; // class for the inactive trigger link $dropdownclosed='dropdownhidden'; // closed dropdown $dropdownopen='dropdownvisible'; // open dropdown $i=0; $count=0; $sels=$('select'); $opts=$('option'); $trigger=('<a href="#"></a>'); function $switchTriggerClass (){ $($trigger).toggleClass($triggeron).toggleClass($triggeroff); } for($i; $i < $opts.length; $i++){ if($($opts[$i]).hasClass('enabled')){ $($opts[$i]).addClass('woo'); } else { $($opts[$i]).addClass('foo'); } } }); 

 <script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script> <tbody> <tr> <td class="label"> <label for="size">Size</label> </td> <td class="value"> <select id="size" class="turnintodropdown" name="attribute_size" data-attribute_name="attribute_size" data-show_option_none="yes"> <option value="">- -</option> <option value="10" class="attached enabled">10</option> <option value="20" class="attached enabled">20</option> <option value="30" class="attached enabled">30</option> <option value="40" class="attached enabled">40</option> <option value="50" class="attached" disabled="">50</option> <option value="60" class="attached" disabled="">60</option> </select> <a class="reset_variations" href="#" style="visibility: hidden;"></a> </td> </tr> </tbody>