In some cases, it may prove useful to use more than one JavaScript library on the same page. As many libraries make use of the $identifier (as it is short and convenient), we need a way to prevent collisions between these uses.
在某些场景下，在一个网页上不仅仅使用一个js库可能是很有用的。由于很多库使用＄标示符（因为他很短而且很方便），我们需要阻止这些库的冲突。
Fortunately, jQuery provides a method called jQuery.noConflict()to return control of the $identifier back to other libraries. Typical usage of jQuery.noConflict()is as follows:
<script src="prototype.js"></script> <script src="jquery.js"></script> <script> jQuery.noConflict(); </script> <script src="myscript.js"></script>幸运的是，jquery提供了一个叫做jQuery.noConflick()的方法把对＄标示符的控制权交给其他的库。jQuery.noConflict()典型的使用方法如下：
<script src="prototype.js"></script> <script src="jquery.js"></script> <script> jQuery.noConflict(); </script> <script src="myscript.js"></script>First, the other library (Prototype in this example) is included. Then, jQuery itself is included, taking over $for its own use. Next, a call to .noConflict()frees up $, so that control of it reverts to the first included library (Prototype). Now in our custom script, we can use both libraries―but whenever we want to use a jQuery method, we need to write jQueryinstead of $as an identifier.
首先，另外一个库被引入（这里用Prototype做例子），然后，jquery自己被引入，拿来＄自己使用。接着，调用.noConflict()函数释放＄的控制权，于是对＄的控制权重新复原到最初被包含的库（Prototype）中。现在我们一般脚本可以使用两个库了，但是无论何时我们想使用一个jquery方法，我们需要写下jQuery作为标示符，而不是＄。
The .ready()method has one more trick up its sleeve to help us in this situation.
The callback function we pass to it can take a single parameter: the jQuery object itself. This allows us to effectively rename it without fear of conflicts, as shown in the following code snippet:
The callback function we pass to it can take a single parameter: the jQuery object itself. This allows us to effectively rename it without fear of conflicts, as shown in the following code snippet:
jQuery(document).ready(function($) {
// In here, we can use $ like normal!
});
Or, using the shorter syntax we learned in the preceding code:jQuery(function($) {
// Code that uses $.
});
.ready()方法有不仅仅一个方法帮助我们处理这种场景。我们传递给他的回调函数可以拥有一个参数：jquery对象自己。这允许我们有效地重命名他，而不用担心冲突，正如下面的代码展示的那样：
jQuery(document).ready(function($) {
// In here, we can use $ like normal!
});
或者，使用我们在之前的代码中学到的更加简短的语法：
jQuery(function($) {
// Code that uses $.
});