为什么不能声明变量，将其转换为整数并在代码中使用该整数？

Question

I am trying to create a playlist of audio files. The html contains three audio tags:

<ul id="myAudio">
    <li>
        <audio class="audio" id="1" controls>
            <source src="_audio/Clear_Vision.mp3" type="audio/mpeg" />
        </audio>
    </li>
    <li>
        <audio class="audio" id="2" controls>
            <source src="_audio/Greensleeves.mp3" type="audio/mpeg" />
        </audio>
    </li>
    <li>
        <audio class="audio" id="3" controls>
            <source src="_audio/Pavane21Sec.mp3" type="audio/mpeg" />
        </audio>
    </li>
</ul>

so far my javascript(jquery) is:

$(document).ready(function(){
    var audioElement = document.createElement('audio');

    var x = 1;
    x = parseInt(x);


    var deisredAudio = $('source:nth(0)').attr('src');

    audioElement.setAttribute('src', deisredAudio);

    $.get();

    audioElement.addEventListener("load", function(){
        audioElement.play();
    }, true);

    $('#playAudio').click(function(){
        audioElement.play();
    });

    $('#pauseAudio').click(function(){
        audioElement.pause();
    });
});

This will play the audio track as long as I have an integer in the $('source:nth(0)') .

This will play the first audio, $('source:nth(1)') will play the second and so on as expected.

What I need to do is insert a variable to eventually create a loop to loop through and play the audio tracks.

When I declare a variable x = 1 , and then insert it into $('source:nth(x)') , it does not work.

Please note that I am self-taught in JavaScript.

Any help or insight will be greatly appreciated.

Answer 1

You need to take it out of quotes and pass it into your :nth() using string concatenation:

$('source:nth(' + x + ')')

...otherwise you're using the character literal "x".