【JS】(+﹏+)~

1

var o = new Object()

var o = new Object // 如果没有参数，括号可以省略

 

 

2

this.init.apply(this, arguments) ???

// 创建类

var Class = function() {

    var klass = function() {

        this.init.apply(this, arguments)

    }

    klass.prototype.init = function() {}

    return klass

}



var Person = new Class()

Person.prototype.init = function() {

}



var person = new Person()

 

what does this usage of apply() means in Javascript

;(function() {

    var Klass = function(arg1, arg2, arg3) {

        this.init(arg1, arg2, arg3)

    }

    Klass.prototype.init = function(arg1, arg2, arg3) {

        console.log(arg1, arg2, arg3)

    }

    var klass = new Klass(1, 2, 3) 

})()



;(function() {

    var Klass = function() {

        this.init.apply(this, arguments)

    }

    Klass.prototype.init = function() {

        console.log(arguments[0], arguments[1], arguments[2])

    }

    var klass = new Klass(1, 2, 3) 

})()



;(function() {

    var Klass = function() {

        this.init(arguments[0], arguments[1], arguments[2])

    }

    Klass.prototype.init = function() {

        console.log(arguments[0], arguments[1], arguments[2])

    }

    var klass = new Klass(1, 2, 3) 

})()

 

 

3

/**

 * 当你读取一个对象的属性时，JS首先会在本地对象中查找这个属性，

 * 如果没有找到，JS开始在对象的原型中查找，

 * 仍未找到还会继续查找原型的原型，

 * 直到查找到Object。prototype

 * 如果找到这个属性，则返回这个值，否则返回undefined

 */

var Person = function() {

    this.say = function() {

        console.log('e')

    }

}

Person.prototype.say = function() {

    console.log('ee')

}

new Person().say() // e