如何使用bootstrap 3获取行中特定列的row类的全宽度

<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.min.css">
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/js/bootstrap.min.js"></script>

<div class="row">
    <div class="col-xs-4">Column 1</div>
    <div class="col-xs-4">Column 2</div>
    <div class="col-xs-4">Column 3</div>
</div>

var columnWidth = $(".row > .col-xs-4:eq(1)").outerWidth();