JAVASCRIPT實現繼承的幾種方式

標籤：JAVASCRIPT實現繼承的幾種方式

對象冒充（多繼承）：
a. 代碼：

function ClassA(sColor) {this.color = sColor;this.sayColor = function () {    console.log(this.color);};}function ClassB(sName) {this.name = sName;this.sayName = function () {    console.log(this.name);};}function ClassC(sColor, sName) {this.newMethod = ClassA;this.newMethod(sColor);delete this.newMethod;this.newMethod = ClassB;this.newMethod(sName);delete this.newMethod;}var objA = new ClassA("blue");var objC = new ClassC("red", "John");objA.sayColor();objC.sayColor();objC.sayName();

b. 輸出：

blueredJohn

call()方法（推薦）：
a. 代碼：

function ClassA(sColor) {this.color = sColor;this.sayColor = function () {    console.log(this.color);};}function ClassB(sName) {this.name = sName;this.sayName = function () {    console.log(this.name);};}function ClassC(sColor, sName) {ClassA.call(this,sColor)ClassB.call(this,sName)}var objA = new ClassA("blue");var objC = new ClassC("red", "John");objA.sayColor();objC.sayColor();objC.sayName();

b. 輸出：

blueredJohn

apply()方法（推薦）：
a. 代碼：

function ClassA(sColor) {this.color = sColor;this.sayColor = function () {    console.log(this.color);};}function ClassB(sName) {this.name = sName;this.sayName = function () {    console.log(this.name);};}function ClassC(sColor, sName) {ClassA.apply(this,new Array(sColor))ClassB.apply(this,new Array(sName))}var objA = new ClassA("blue");var objC = new ClassC("red", "John");objA.sayColor();objC.sayColor();objC.sayName();

b. 輸出：

blueredJohn

原型鏈（單繼承）：
a. 代碼：

function ClassA(color) {this.color = colorthis.sayColor = function () {    console.log(this.color);};}function ClassB(name) {this.name = namethis.sayName = function () {    console.log(this.name);};}ClassB.prototype = new ClassA("red");var objA = new ClassA("blue");var objB = new ClassB("John");objA.sayColor();objB.sayColor();objB.sayName();

b. 輸出：

blueredJohn

混用對象冒充與原型鏈（多繼承）：
a. 代碼：

function ClassA(sColor) {this.color = sColor;this.sayColor = function(){    console.log(this.color)}}function ClassB(sName) {this.name = sName;this.sayName = function(){    console.log(this.name)}}function ClassC(sColor, sName) {ClassA.call(this, sColor);ClassB.call(this, sName);}ClassC.prototype = new ClassA();ClassC.prototype = new ClassB();var objA = new ClassA("blue");var objC = new ClassC("red", "John");objA.sayColor();objC.sayColor();objC.sayName();

b. 輸出：

blueredJohn

說明：

推薦使用call()方法或apply()方法

JAVASCRIPT實現繼承的幾種方式