本文讨论了 ES5 中的继承方法，重点关注三种主要方法：基于原型的继承、构造函数继承和寄生继承。文章解释了每种方法的优点和缺点，提供了代码例如
在ES5中，继承可以通过几种方法来实现：
这是最常见的方法在 ES5 中。它涉及创建一个基类（父类），然后通过创建继承基类的属性和方法的新对象来“子类化”它。这是通过操作子类对象的 __proto__ 属性来完成的。__proto__ property of the subclass objects.
<code class="javascript">const Animal = {
eat() {
console.log("Eating...");
}
};
const Dog = {
__proto__: Animal,
bark() {
console.log("Woof!");
}
};
const myDog = Object.create(Dog);
myDog.eat(); // logs "Eating..."
myDog.bark(); // logs "Woof!"</code>This approach involves creating a base class constructor function and then extending it by defining a new constructor function that takes the base class constructor as an argument and adds additional properties and methods.
<code class="javascript">function Animal() {
this.eat = function() {
console.log("Eating...");
}
}
function Dog(name) {
Animal.call(this);
this.name = name;
this.bark = function() {
console.log("Woof!");
}
}
const myDog = new Dog("Luna");
myDog.eat(); // logs "Eating..."
myDog.bark(); // logs "Woof!"</code>This approach involves creating a temporary object that inherits from the base class and then uses that object to create the desired subclass. It is similar to prototype-based inheritance, but instead of modifying the __proto__
<code class="javascript">const Animal = {
eat() {
console.log("Eating...");
}
};
const Dog = (function() {
function AnimalProxy() {}
AnimalProxy.prototype = Animal;
const proxy = new AnimalProxy();
proxy.bark = function() {
console.log("Woof!");
}
return proxy;
})();
const myDog = Object.create(Dog);
myDog.eat(); // logs "Eating..."
myDog.bark(); // logs "Woof!"</code>以上是es5实现继承的方法的详细内容。更多信息请关注PHP中文网其他相关文章！
