javascript “类型错误：$(...) 为空”这是怎么回事？
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"TypeError: $(...) is null" What's Going On?
提问by Joshua
Firebug is giving the error:
Firebug 给出了错误：
TypeError: $(...) is null
$('#menu img').hover(
I have no idea why. The seemingly problematic script is this which replaces an image when the cursor hovers over an image:
我不知道为什么。看似有问题的脚本是当光标悬停在图像上时替换图像：
$(document).ready(function()
{
var storeNormalPath;
$('#menu img').hover(
function()
{
storeNormalPath = $(this).attr('src');
var imgArray = $(this).attr('src').split('.jpg');
$(this).attr('src', imgArray[0]+'Hover.jpg');
},
function()
{
$(this).attr('src', storeNormalPath);
}
).click (function()
{
//empty now
});
});
回答by dayala
After some looking over your page using chrome's console, it looks that even $(document)is returning null.
jQuery(document)however, works, which suggests there is something in conflict with jQuery's $ operator.
在使用 chrome 的控制台查看您的页面后，它看起来甚至$(document)返回 null。
jQuery(document)但是，有效，这表明与 jQuery 的 $ 运算符存在冲突。
(Source: I would direct you to this question: $.document is null)
（来源：我会引导你回答这个问题：$.document is null）
Seeing that you have both jquery-1.5.1.min.jsAND jquery.1.4.2.jsreferenced in your page header, perhaps that could be the reason of the conflict? Have you tried loading only one of them?
看到您的页眉中同时引用了jquery-1.5.1.min.js和jquery.1.4.2.js，也许这可能是冲突的原因？你试过只加载其中之一吗？
Let us know if that helps, sorry I couldn't be more help. Good luck!
如果这有帮助，请告诉我们，对不起，我无法提供更多帮助。祝你好运！
