值、原型和属性的区别 [英] Difference of the value, prototype and property

问题描述

好的！首先，这个问题来自一个在 jQuery 世界中挖掘得太深(并且可能迷路)的人.

OK! First of all this question comes from a man who digs too deep (and posibly get lost) in the jQuery universe.

在我的研究中，我发现 jquery 的主要模式是这样的(如果需要更正是好的):

In my reserch I discovered the jquery's main pattern is something like this (If needed correction is wellcomed):

(function (window, undefined) {

   jQuery = function (arg) {
      // The jQuery object is actually just the init constructor 'enhanced'
      return new jQuery.fn.init(arg);
   },
   jQuery.fn = jQuery.prototype = {
      constructor: jQuery,
      init: function (selector, context, rootjQuery) {
         // get the selected DOM el.
         // and returns an array
      },
      method: function () {
         doSomeThing();
         return this;
      },
      method2: function () {
         doSomeThing();
         return this;,
         method3: function () {
            doSomeThing();
            return this;
         };

         jQuery.fn.init.prototype = jQuery.fn;

         jQuery.extend = jQuery.fn.extend = function () {

            //defines the extend method 
         };
         // extends the jQuery function and adds some static methods 
         jQuery.extend({
            method: function () {}

         })

      })

当 $ 启动时 jQuery.prototype.init 启动并返回一个元素数组.但我无法理解它如何添加像 .css 或 .hide 等的 jQuery 方法.到这个数组.

When $ initiates the jQuery.prototype.init initiates and returns an array of elements. But i could not understand how it adds the jQuery method like .css or .hide ,etc. to this array.

我得到了静态方法.但是无法获得所有这些方法的返回方式和元素数组.

I get the static methods. But could not get how it returns and array of elements with all those methods.

推荐答案

我也不喜欢那种模式.它们有一个 init 函数，它是所有 jQuery 实例的构造函数——jQuery 函数本身只是一个用 new 创建对象的包装器:

I don't like that pattern either. They have an init function, which is the constructor of all jQuery instances - the jQuery function itself is just a wrapper around that object creation with new:

function jQuery(…) { return new init(…); }

然后，他们将这些实例的方法添加到 init.prototype 对象中.该对象在 jQuery.fn 中作为接口公开.此外，他们将 jQuery 函数的 prototype 属性设置为该对象 - 对于那些不使用 fn 属性的人.现在你有

Then, they add the methods of those instances to the init.prototype object. This object is exposed as an interface at jQuery.fn. Also, they set the prototype property of the jQuery function to that object - for those who don't use the fn property. Now you have

jQuery.prototype = jQuery.fn = […]init.prototype

但他们也做了两件[奇怪的]事情:

But they also do two [weird] things:

• 覆盖原型对象的constructor属性，将其设置为jQuery函数
• 在 jQuery.fn 上公开 init 函数 - 它自己的原型.这可能允许扩展 $.fn.init 函数，但非常混乱

• overwriting the constructor property of the prototype object, setting it to the jQuery function
• exposing the init function on jQuery.fn - its own prototype. This might allow Extending $.fn.init function, but is very confusing

我认为他们需要/想要做这一切以防止万无一失，但他们的代码一团糟——从那个对象文字开始，然后分配初始化原型.

I think they need/want to do all this to be fool-proof, but their code is a mess - starting with that object literal and assigning the init prototype things afterwards.

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