JavaScript Reflect.construct() method in JavaScript is used to call a new target. It gives also the added option to specify a different prototype.
Syntax:
Reflect.construct(target, argumentsList, newTarget)
Parameters: This method accepts three parameters as mentioned above and described below:
- target: This parameter is the target function that is going to be called.
- ArgumentsList: This parameter is an array-like object specifying the argument with which the target should be called.
- newTarget: It is an optional parameter. The constructor whose prototype should be used.
Return Value: This method returns a new instance of the target.
Exceptions: A TypeError is an exception given as the result when the target is not a constructor.
The below examples illustrate the Reflect.construct() method in JavaScript:
Example 1: This example shows the basic use of the Reflect.construct() method in JavaScript.
javascript
function func1(a, b, c) {Â Â Â Â this.sum = a + b + c;}Â
const args = [1, 2, 3];const object1 = new func1(...args);const object2 = Reflect.construct(func1, args);Â
console.log(object2.sum);Â
console.log(object1.sum);Â
function func2(a, b, c) {Â Â Â Â this.sum = a + b + c;}const args2 = [1, 4, 3];const args3 = [1, 2, 3];const object3 = new func1(...args);const object4 = Reflect.construct(func2, args2);console.log(object4.sum);console.log(object3.sum); |
6 6 8 6
Example 2: This example shows the basic use of the Reflect.construct() method in JavaScript.
javascript
function OneClass() {Â Â Â Â this.name = 'one'}Â
function OtherClass() {Â Â Â Â this.name = 'other'}const args = [1, 2, 3];Â
let obj1 = Reflect.construct(OneClass, args, OtherClass)Â
let obj2 = Object.create(OtherClass.prototype)OneClass.apply(obj2, args)Â
console.log(obj1.name)console.log(obj2.name)Â
console.log(obj1 instanceof OneClass)console.log(obj2 instanceof OneClass)Â
console.log(obj1 instanceof OtherClass)console.log(obj2 instanceof OtherClass) |
one one false false true true
Supported Browsers:
The browsers are supported by JavaScript Reflect.apply() Methods are listed below:
- Google Chrome 49 and above
- Edge 12 and above
- Firefox 42 and above
- Opera 36 and above
- Safari 10 and above
We have a complete list of Javascript Reflects methods, to check those go through the JavaScript Reflect Reference article.
