TypeError：不是构造函数

我正在尝试使用基于OOP的javascript / jQuery。 我想将所有JS函数放在一个类中，因此可以轻松覆盖/挂钩。

我试过一个简单的OOP代码，但它给出了类型错误：不是构造函数。 请查看我的代码并指导我的代码有什么问题，以及如何解决它。

var myTestClass = { testAttribute : 'test', // atttribute testMethod : function(){ alert( testAttribute); } }; var my = new myTestClass(); my.testMethod(); 

谢谢

Answer 1

查看提醒：

 var myTestClass = { testAttribute: 'test', testMethod: function () { alert(this.testAttribute); } }; myTestClass.testMethod(); 

另一种方法：

 function myTClass(){ var testAttribute = 'test'; this.testMethod = function () { alert(testAttribute); }; } var obj = new myTClass(); obj.testMethod(); 

延迟inheritance示例：

 function myTClass(){ this.testMethod = function () { alert(this.testAttribute); }; } myTClass.prototype.testAttribute = 'test'; var obj = new myTClass(); obj.testMethod(); function derivedTClass() { myTClass.call(this); this.testMethod = function () { alert('derived ' + this.testAttribute); }; } derivedTClass.prototype = Object.create(myTClass.prototype); var obj2 = new derivedTClass(); obj2.testMethod(); derivedTClass.prototype.constructor = derivedTClass; 

Answer 2

 var myTestClass = { testAttribute : 'test', testMethod : function(){ alert(myTestClass.testAttribute); } }; var my = Object.create(myTestClass); my.testMethod(); 

要么

 var myTestClass1 = function () { this.options = {}; this.testAttribute = "test"; }; myTestClass1.prototype.testMethod = function () { var self = this; alert(self.testAttribute); } var x = new myTestClass1(); x.testMethod(); 

或者如果你使用jQuery

 (function ($) { 'use strict'; var MyTestClassObject = { testMethod: function () { var self = this; alert($.fn.myTestClass.options.testAttribute); }, init: function (options, elem) { $.fn.myTestClass.options = $.extend({}, $.fn.myTestClass.options, options); } }; $.fn.myTestClass = function (options) { var out = Object.create(MyTestClassObject); out.init(options, this); return out; }; $.fn.myTestClass.options = { testAttribute : 'test' //default }; }(jQuery)); var x = $.fn.myTestClass({testAttribute: 'overwrite'}); x.testMethod(); 

或者使用inheritance和抽象类

 var GElement = function (x, y) { this.x; this.y; throw "can not instantiate GElement"; }; GElement.prototype.init = function (x, y) { this.x = x; this.y = y; } GElement.prototype.draw = function () { throw "method draw of type GElement is abstract"; } var Circle = function () { this.radius; }; Circle.prototype = Object.create(GElement.prototype); Circle.prototype.init = function (x, y, radius) { this.x = x; this.y = y; this.radius = radius; } Circle.prototype.draw = function() { alert('circle draw { x: ' + this.x + ", y: " + this.y + ", radius: " + this.radius + " }"); }; var Rectangle = function () { this.width; this.height; }; Rectangle.prototype = Object.create(GElement.prototype); Rectangle.prototype.init = function (x, y, width, height) { this.x = x; this.y = y; this.width = width; this.height = height; } Rectangle.prototype.draw = function() { alert('rectangle draw { x: ' + this.x + ", y: " + this.y + ", width: " + this.width + ", height: " + this.height + " }"); }; var b = new Circle(); b.init(1,2,3); var r = new Rectangle(); r.init(5,5,12,7); b.draw(); r.draw(); 

或者，与es6

//文件test.js

 class TestClass { constructor (init) { this._val = init; } get val () { return this._val; } set val (arg) { this._val = arg; } doSomething () { console.log('Wow'); } } export default TestClass; 

//文件test2.js

 import TestClass from "./test.js"; const COLORS = new Set(['Red', 'Green', 'Blue']); class InheritedTestClass extends TestClass { static isValidColor (color) { return COLORS.has(color); } constructor (init, color) { super(init); if (InheritedTestClass.isValidColor(color)) { this.color = color; } else { throw TypeError(`InheritedTestClass.constructor [error]: color "${color}" is undefined`); } } doSomething () { console.log("Bark"); } } export default InheritedTestClass; 

//文件main.js

 import TestClass from '.test.js'; import InheritedTestClass from '.test2.js'; let test1 = new TestClass(10); let test2 = new InheritedTestClass(12, 'Red'); test1.doSomething(); test2.doSomething(); test2.val = 30; console.log(test2.val); if (test1 instanceof TestClass) { console.log(true); } if (test2 instanceof TestClass) { console.log(true); } if (test2 instanceof InheritedTestClass) { console.log(true); } if (!(test1 instanceof InheritedTestClass)) { console.log(true); }