jQuery:检查一个对象是否有类

col*_*unn 5 html javascript css jquery

试图检查对象是否有类.看起来很简单,但我无法让它工作.这是我的代码:

使用Javascript

$('ul.nav li').click(function(){    
    if $(this).hasClass('selected') {
        alert('This is selected!');
    }

    else {
        alert('This is not selected!');
    }
});

$('ul.nav li:first-child').addClass('selected');
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HTML

<ul class="nav">
    <li>Who we work for</li>
    <li>Articles and interviews</li>
    <li>Job openings</li>
    <li>What the #%!$@ is Post Typography?</li>
</ul>

<ul class="content">
    <li>This is who we work for.</li>
    <li>These are articles and interviews.</li>
    <li>These are our job openings.</li>
    <li>This is some info about Post Typography.</li>
</ul>
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YMM*_*MMD 25

if $(this).hasClass('selected') {
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应该

if($(this).hasClass('selected')){
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当您查看浏览器的错误控制台时,可以很容易地看到这一点.:-)