How to useconstructor property in Javascript

Q: How to useconstructor property in Javascript

instanceof operator: It checks whether the LHS (left-hand side) object is an object of the RHS (right-hand side) class or not. If the object is of that particular class, then it returns true otherwise false.

Approach 2: Using instanceof operator

Using the constructor property to check if a variable is a string literal or an object of the String constructor, the constructor property of the input matches String, it is considered a string literal. If the constructor property matches String.prototype.constructor, it is considered an object of the String constructor.

Example: In this example, the check() function uses the constructor property to determine whether the input is a string literal or an object of the String constructor

Javascript

function check(str) {
    if (str.constructor === String) {
        return "It is a string literal";
    } else if (str.constructor === String.prototype.constructor) {
        return "It is an object of string";
    } else {
        return "Another type";
    }
}
 
// Pass a string literal
console.log(check("Hello, Geeks"));
 
// Pass an object of string
let result = new String("Hello, w3wiki");
console.log(check(result));

Output

It is a string literal
It is a string literal

How to test a string as a literal and as an object in JavaScript ?

In this article, we learn how to test a string as a literal and as an object using JavaScript.

Tags:

#javascript-object #JavaScript-Questions #JavaScript #Web Technologies

Approach 2: Using instanceof operator

How to useconstructor property in Javascript

Javascript

How to test a string as a literal and as an object in JavaScript ?

Similar Reads