jquery - 根据班级获取 td 总数？

Question

我有一个动态生成的表，看起来像这样：

<table id="mytable">
    <thead>
        <tr>
            <td>col1</td>
            <td>col2</td>
            <td>col3</td>
        </tr>
    </thead>
    <tbody>
        <tr>
            <td>col1</td>
            <td class="col2">1</td>
            <td class="col3">2</td>
        </tr>
        <tr>
            <td>col1</td>
            <td class="col2">7</td>
            <td class="col3">4</td>
        </tr>
        <tr>
            <td>col1</td>
            <td class="col2">col2</td>
            <td class="col3">col3</td>
        </tr>
    </tbody>
    <tfoot>
        <tr>
            <td>Totals</td>
            <td id="col2total"></td>
            <td id="col3total"></td>
        </tr>
    </tfoot>
</table>

如何获得tds 中具有类的值col2的总和并将总和添加到tdid col2total？由于此表是动态生成的，我不知道tr在tbody.

Answer 1

试试这个：

var total = 0;
$(".col2").each(function() {
    total += parseFloat('0' + $(this).text(), 10);
})
$("#col2total").text(total);

Answer 2

var total = 0;
$("td.col2").each(function() {
    total += parseFloat($(this).text()) || 0;
});

$("#col2total").text(total);

Answer 3

$(document).ready(function(){ 
    var sum = 0; 
    $('.col2').each(function() { 
        sum += Number($(this).val()); 
    });

    $("#col2total").text(sum); 
});