[英]Return value of this from Javascript constructor function, when another constructor is returned
為什么這指向父類,而不是窗口對象? 這不是Klass函數的功能。
function Class() {
function Klass() {
this.color="blue"
}
Klass.prototype.value = this; // when called this is pointing to Class
console.log(this) // "Class"
return Klass;
}
var One = new Class(); // new constructor is returned
var Two = new One(); // creating new object
Two.value
- Class // why ?
Two.value instanceof Class // true
Two.value包含Class的實例,而不是對該Class的引用。
function Class() {
function Klass() {
this.color="blue"
}
Klass.prototype.value = this; // this is in a closure
console.log(this) // "Class"
return Klass;
}
var One = new Class(); // new constructor is returned
var Two = new One(); // creating new object
Two.value
- Class // this is always refer to "One"
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