我无法将课程添加到第n个孩子

Question

HTML:

        <div id="brojac-poteza" style="clear:both;padding-top:40px;padding-left:60px;padding-right:40px">
            <div class="round-end darker-back card-choice">1</div>
            <div class="darker-back card-choice">2</div>
            <div class="darker-back card-choice">3</div>
            <div class="darker-back card-choice">4</div>
            <div class="darker-back card-choice">6</div>
            <div class="darker-back card-choice">5</div>
            <div class="darker-back card-choice">7</div>
            <div class="darker-back card-choice">8</div>
            <div class="darker-back card-choice">9</div>
            <div class="darker-back card-choice">10</div>
        </div>

script.js (above this code I set var g = 1; )

g += 1;

$('#brojac-poteza:nth-child(g)').addClass('round-end');

When I test it says Uncaught Error: Syntax error, unrecognized expression: :nth-child

Answer 1

更改为

$('#brojac-poteza:eq('+g+')').addClass('round-end');

Answer 2

First you need to use variable g not g as string and find nth of children not on root:

 var g = 5; $('#brojac-poteza div:nth-child(' + g + ')').addClass('round-end'); 

 .round-end { background-color: red; } 

 <script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script> <div id="brojac-poteza" style="clear:both;padding-top:40px;padding-left:60px;padding-right:40px"> <div class="round-end darker-back card-choice">1</div> <div class="darker-back card-choice">2</div> <div class="darker-back card-choice">3</div> <div class="darker-back card-choice">4</div> <div class="darker-back card-choice">6</div> <div class="darker-back card-choice">5</div> <div class="darker-back card-choice">7</div> <div class="darker-back card-choice">8</div> <div class="darker-back card-choice">9</div> <div class="darker-back card-choice">10</div> </div> 

Answer 3

You can try these solution also :-

$('#brojac-poteza .darker-back:nth-child(' + g + ')').addClass('round-end');

It may help you.

Answer 4

You can also try to count the .darker-black elements by doing this for example:

$(function() {
    var numItems = $('#brojac-poteza .darker-back').length; /* Count items */
    var odd = 2; /* Change the steps here if you like to */

    /* Now loop it, and skip 1 step, 1, 3, 5 ... */
    for(g = 1; g < numItems; g+=odd) {
        $('#brojac-poteza div:nth-child(' + g + ')').addClass('test');
        console.log(g);
    }
});

See this fiddle: https://jsfiddle.net/r2ncLpLb/1/

I hope this will work for you either :)