Jquery each():回调中的变量总是有最后一个值? [英] Jquery each(): variable in callback always has last value?

问题描述

似乎无法弄清楚这里发生了什么.

<ul id="navList"><li class="navItem"><a href="http://www.jacobsmits.com/placeholderRX.html">发现</a></li><li class="navItem"><a href="http://www.jacobsmits.com/placeholderRX/documentation.html">文档</a></li><li class="navItem"><a href="http://www.jacobsmits.com/placeholderRX/download.html">下载</a></li><li class="navItem"><a href="http://www.jacobsmits.com/placeholderRX/donate.html">捐赠</a></li><script type="text/javascript">$('.navItem').each(function() {$link = $(this).children('a');$link.hover(功能() {$link.css('width', '224px');},功能() {$link.css('width', '192px');})});

http://jsfiddle.net/Sth3Z/

它应该对每个链接都这样做，而不是无论悬停在哪个链接上，它都只会更改最后一个链接.

解决方案

在 $link 之前添加 var: http://jsfiddle.net/Sth3Z/1/

 $('.navItem').each(function() {var $link = $(this).children('a');//`var` 添加

目前，您正在声明一个全局变量，它将在循环中的每次迭代中被覆盖.

Can't seem to figure out what's going on here.

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    </ul>
    <script type="text/javascript">
        $('.navItem').each(function() {
            $link = $(this).children('a');
            $link.hover(
                function() {
                    $link.css('width', '224px');
                },
                function() {
                    $link.css('width', '192px');
                }
            )
        });            
    </script>
</div>

http://jsfiddle.net/Sth3Z/

It should be doing it for each link, instead it only changes the last link no matter which one is being hovered over.

解决方案

Add var before $link: http://jsfiddle.net/Sth3Z/1/

    $('.navItem').each(function() {
        var $link = $(this).children('a');   // `var` added

Currently, you're declaring a global variable, which will be overwritten at each iteration in the loop.

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