JavaScript Boolean object represents two values, either “true” or “false“. To create an object with Boolean and set the Boolean value “true” or “false”, which are the Boolean literals. JavaScript Boolean object is a member of global objects and a wrapper class.
var x = new Boolean(false);
var x = new Boolean(true);
Do not confuse the primitive Boolean
values true
and false
with the true
and false
values of the Boolean
object.
var x = new Boolean(false);
if (x) {
// this code is executed
}
This behavior does not apply to Boolean
primitives. For example, the condition in the following if
statement evaluates to false
:
var x = false;
if (x) {
// this code is not executed
}
Boolean object in JavaScript
Simple example code.
<!DOCTYPE html>
<html>
<body>
<script>
var a = new Boolean(false)
console.log("Object constructed : " + a.constructor);
console.log(a)
console.log(!a)
</script>
</body>
</html>
Output:
Boolean Objects Property
Name | Description | Version |
---|---|---|
constructor | Specifies the function that creates an object’s prototype. | Implemented in JavaScript 1.1 |
prototype | Use to add new properties and methods to a boolean object. | Implemented in JavaScript 1.1 |
Boolean Objects Methods
Name | Description | Version |
---|---|---|
toSource | Returns a string which represents the source code of a boolean object. | Implemented in JavaScript 1.1 |
toString | Returns a string representing the specified boolean object. | Implemented in JavaScript 1.1 |
valueof | Returns the primitive value of a boolean object. | Implemented in JavaScript 1.1 |
Boolean Object False
JavaScript Boolean Object will have the initial value as false if the value provided at the time of object creation is 0, -0, NaN
, null
, undefined
, false, empty string, or even if no value is provided because the default value is also false.
let obj1 = new Boolean();
let obj2 = new Boolean(0);
let obj3 = new Boolean(null);
let obj4 = new Boolean('');
let obj5 = new Boolean(false);
Boolean Object True
Apart from the values specified above, for which the initial value of the Boolean object is false, all other values will set the value as true. Let’s take a few examples,
let obj1 = new Boolean(true);
let obj2 = new Boolean('true');
let obj3 = new Boolean('false');
let obj4 = new Boolean('hello');
let obj5 = new Boolean([]);
let obj6 = new Boolean({});
Comment if you have any doubts or suggestions on this JS Object topic.
Note: The All JS Examples codes are tested on the Firefox browser and the Chrome browser.
OS: Windows 10
Code: HTML 5 Version