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Javascript &引用;“新狗”;或;新狗();_Javascript - Fatal编程技术网

Javascript &引用;“新狗”;或;新狗();

Javascript &引用;“新狗”;或;新狗();,javascript,Javascript,使用或不使用括号“实例化”JavaScript“类”之间有什么区别 function Animal(name) { this.name = name; } Animal.prototype.sayName = function() { console.log(this.name); }; function Dog(name) { Animal.call(this, name); } Dog.prototype = new Animal(null); Dog.p

使用或不使用括号“实例化”JavaScript“类”之间有什么区别

function Animal(name) {
     this.name = name;
}

Animal.prototype.sayName = function() {
     console.log(this.name);
};

function Dog(name) {
     Animal.call(this, name);
}

Dog.prototype = new Animal(null);
Dog.prototype.bark = function() {
     console.log("Woof!");
};

var d = new Dog


这个问题已经提出了

只要构造函数不带参数,它们之间就没有区别。也就是说:调用newdog(没有括号)就像调用newdog()没有参数一样

var d = new Dog()