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Boolean in Javascript-tutorial

In JavaScript, the boolean is a primitive data type used to represent logical values

true

false

Booleans are most commonly used in conditional statements (like if, switch) to control the flow of a program.

How to Create Boolean Objects

While you can use primitive boolean values directly (true or false), JavaScript also allows you to create Boolean objects using the Boolean constructor.

var b = new Boolean(true);

By default, the value is false if no argument is passed.

Example:

<!DOCTYPE html>
<html>

<body>
    <script>
        document.write(10 < 20); // true
        document.write("<br>");
        document.write(10 < 5);  // false
    </script>
</body>

</html>

Output

boolean Properties

constructor

Returns a reference to the Boolean function that created the object's prototype.

var b = new Boolean(true);
console.log(b.constructor);  // Output: ƒ Boolean() { [native code] }

prototype

Allows you to add new properties or methods to all Boolean objects.

Boolean Methods

JavaScript's Boolean object inherits some useful methods from the generic object prototype, like

toString() - Converts boolean value to string ("true" or "false").

valueOf() - Returns the primitive value (true or false).

Example:

var b = new Boolean(false);

console.log(b.toString()); // "false"
console.log(b.valueOf());  // false

Key Point

Booleans represent only two values: true or false.

Boolean objects (new Boolean()) are rarely needed; primitive values are usually sufficient.

Use booleans in conditions to control logic in your program.