使用jquery的具有相同类的div的数量

Question

如何使用jquery

查找具有特定类名的div数

就像这里我想得到的结果为2为类名“failedtest”。我也想通过外部div（1285766787423container）的id来访问它们

<div id="1285766787423container" class="container">
    <div class="row">
        <div class="cell1">
        </div>
        <div class="failedtest">
        </div>
    </div>
    <div style="display: none;" class="row">
        <div class="cell1">
        </div>
        <div class="failedtest">
        </div>
    </div>
    <div style="display: none;" class="row">
        <div class="cell1">
        </div>
        <div class="cell2">
        </div>
    </div>
    <div style="display: none;" class="row">
        <div class="cell1">
        </div>
        <div class="cell2">
        </div>
    </div>
</div>

    <div id="1285766787423container" class="container">
    <div class="row">
        <div class="cell1">
        </div>
        <div class="failedtest">
        </div>
    </div>
    <div style="display: none;" class="row">
        <div class="cell1">
        </div>
        <div class="failedtest">
        </div>
    </div>
    <div style="display: none;" class="row">
        <div class="cell1">
        </div>
        <div class="cell2">
        </div>
    </div>
    <div style="display: none;" class="row">
        <div class="cell1">
        </div>
        <div class="cell2">
        </div>
    </div>
</div>

Answer 1

var numberOfFailedDivs = $('#1285766787423container .failedtest').length;

或者如果您只想要此类的div元素：

var numberOfFailedDivs = $('#1285766787423container div.failedtest').length;

Answer 2

$("#1285766787423container div.failedtest").size();

Answer 3

尝试

$("#1285766787423container div.failedtest").length;

Answer 4

$("#1285766787423container div.failedtest").size();