javascript - JavaScript中“ $”符号的含义是什么(What is the meaning of “$” sign in JavaScript)

Question

In the following JavaScript code there is a dollar ( $ ) sign.(在以下JavaScript代码中，有一个美元（ $ ）符号。)

What does it mean?(这是什么意思？) $(window).bind('load', function() { $('img.protect').protectImage(); });   ask by coderex translate from so

Answer 1

Your snippet of code looks like it's referencing methods from one of the popular JavaScript libraries (jQuery, ProtoType, mooTools, and so on).(您的代码段看起来像是来自一种流行的JavaScript库（jQuery，ProtoType，mooTools等）的引用方法。)

There's nothing mysterious about the use of $ in JavaScript.(在JavaScript中使用$并没有什么神秘之处。) $ is simply a valid JavaScript identifier.($只是有效的JavaScript标识符。) JavaScript allows upper and lower letters, numbers, and $ and _ .(JavaScript允许使用大小写字母，数字以及$和_ 。) The $ was intended to be used for machine-generated variables (such as $0001 ).($打算用于机器生成的变量（例如$0001 ）。) Prototype, jQuery, and most javascript libraries use the $ as the primary base object (or function).(原型，jQuery和大多数javascript库都使用$作为主要基础对象（或函数）。) Most of them also have a way to relinquish the $ so that it can be used with another library that uses it.(他们中的大多数人也有放弃$的方法，以便可以将其与使用它的另一个库一起使用。) In that case you use jQuery instead of $ .(在这种情况下，您将使用jQuery而不是$ 。) In fact, $ is just a shortcut for jQuery .(实际上， $只是jQuery的快捷方式。)