Closure Libary 源码分析

本文主要是介绍Closure Libary 源码分析，希望对大家解决编程问题提供一定的参考价值，需要的开发者们随着小编来一起学习吧！

1. Closure 继承

 

1.1 goog.inherits

goog.inherits = function(childCtor, parentCtor) {function tempCtor() { };   // 声明临时函数 tempCtortempCtor.prototype = parentCtor.prototype; // 临时函数的原型指向父构造函数的原型childCtor.superClass_ = parentCtor.prototype; //给子对象构造函数添加superClass_属性，指向父对象构造函数的原型对象childCtor.prototype = new tempCtor(); // 子对象的原型指向 tempCtor的实例childCtor.prototype.constructor = childCtor;   // 子对象原型对象的构建函数指向自己//子构造函数绑定base方法，调用父构造函数原型对象方法childCtor.base = function(me, methodName, var_args) {var args = new Array(arguments.length - 2);for (var i = 2; i < arguments.length; i++) {args[i - 2] = arguments[i]; //获取参数}//执行父对象的方法return parentCtor.prototype[methodName].apply(me, args);};};

 

通过goog.inherits()完成了：

1. 干净的继承父构造函数的原型对象.

2. 增强子构造函数，可以通过childCtor的base方法和所需方法名调用父构造函数原型对象的方法。

3. 为子构造函数新加了一个属性，指向父构造函数的原型对象。

 

参考链接： https://www.cnblogs.com/vivihoo03/p/5651020.html

1.2 goog.base

base: function (me, opt_methodName, var_args) {var caller = arguments.callee.caller; // 这个属性保存着调用当前函数的函数的引用if (caller.superClass_) {// Copying using loop to avoid deop due to passing arguments object to// function. This is faster in many JS engines as of late 2014.var ctorArgs = new Array(arguments.length - 1);for (var i = 1; i < arguments.length; i++) {ctorArgs[i - 1] = arguments[i];}// This is a constructor. Call the superclass constructor.return caller.superClass_.constructor.apply(me, ctorArgs);}// Copying using loop to avoid deop due to passing arguments object to// function. This is faster in many JS engines as of late 2014.var args = new Array(arguments.length - 2);for (var i = 2; i < arguments.length; i++) {args[i - 2] = arguments[i];}var foundCaller = false;for (var ctor = me.constructor;ctor; ctor = ctor.superClass_ && ctor.superClass_.constructor) {if (ctor.prototype[opt_methodName] === caller) {foundCaller = true;} else if (foundCaller) {return ctor.prototype[opt_methodName].apply(me, args);}}// If we did not find the caller in the prototype chain, then one of two// things happened:// 1) The caller is an instance method.// 2) This method was not called by the right caller.if (me[opt_methodName] === caller) {return me.constructor.prototype[opt_methodName].apply(me, args);} else {console.log('goog.base called from a method of one name ' +'to a method of a different name');}}

参考链接： https://www.cnblogs.com/vivihoo03/p/5653073.html

这篇关于Closure Libary 源码分析的文章就介绍到这儿，希望我们推荐的文章对编程师们有所帮助！

---