如何检测至少一个li.tst列表项是否具有.count类,然后显示.msg除法?
<ul>
<li class="tst 1 na">li</li>
<li class="tst 2 na">li</li>
<li class="tst 3 count">li count</li>
<li class="tst 4 na">li</li>
</ul>
<div class="msg" style="display: none;">has count</div>
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例子:
有计数: 真:
<ul>
<li class="tst 1 count">li</li>
<li class="tst 2 na">li</li>
<li class="tst 3 count">li count</li>
<li class="tst 4 na">li</li>
</ul>
<div class="msg" style="display: block;">has count</div>
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有计数:假:
<ul>
<li class="tst 1 na">li</li>
<li class="tst 2 na">li</li>
<li class="tst 3 na">li count</li>
<li class="tst 4 na">li</li>
</ul>
<div class="msg" …Run Code Online (Sandbox Code Playgroud)