问题描述
在中,有一段代码如下所示:
In this video there is a snippet of code that goes something like this:
if (jQuery) {jQuery(function() {
// ...
})}
我从未见过 jQuery()
之前的功能(然后再说,我不是一个精明的jQuery用户),它做了什么?它是默认使用jQuery发布的还是特定于?由于通常的 $(窗口).load()
代码段丢失且代码有点相似,我猜它是一个快捷方式/别名:
I've never seen the jQuery()
function before (then again, I'm not a savvy jQuery user), what does it do? Does it ship by default with jQuery or is it specific to IxEdit? Since the usual $(window).load()
snippet is missing and the code is somewhat similar I'm guessing it's a shortcut / alias to:
$(window).load(function() {
// ...
)}
我是对的吗?那个 jQuery
变量是什么?它有什么作用?他为什么要检查它?
Am I right? Also what is that jQuery
variable? What does it hold? And why is he checking it?
推荐答案
$()是jQuery()的别名,定义为:
$() is an alias for jQuery(), defined as:
// Expose jQuery to the global object
window.jQuery = window.$ = jQuery;
有一个特殊情况定义为$( )或jQuery()被调用,第一个参数是函数:
there is a special case defined when $() or jQuery() is called with the first argument being a function:
// HANDLE: $(function)
// Shortcut for document ready
} else if ( jQuery.isFunction( selector ) ) {
return rootjQuery.ready( selector );
}
有时$可以与定义相同功能的其他库(如原型)发生冲突,所以如果你打电话
sometimes $ can conflict with other libraries (like prototype) that define the same function, so if you call
jQuery.noConflict();
它会删除$别名,将其设置回原来的值,基本上是:
it will remove the $ alias, setting it back to the original value found, essentially:
window.$ = _$;
这篇关于jQuery中的jQuery()函数有什么作用?的文章就介绍到这了,希望我们推荐的答案对大家有所帮助,也希望大家多多支持!