JavaScript has a Boolean data type and a boolean variable value is one that can either be TRUE or FALSE. The boolean function returns the boolean value of a variable.
- The boolean primitive type that has two values of
trueandfalse. - The
Booleanobject is an object wrapper for a boolean value. - Use the
Boolean()function to find out if an expression (or a variable) is true:
JavaScript boolean examples
Simple example code boolean primitive type. The following example declares two variables that hold boolean values of false and true:
<!DOCTYPE html>
<html>
<body>
<script>
let isPending = false;
let isDone = true;
console.log("isPending", isPending, typeof(isPending))
console.log("isDone", isDone, typeof(isDone))
</script>
</body>
</html>Output:
Boolean object
Use the Boolean() function to convert a string into a boolean value. Because the string is not empty, it returns true.
let a = Boolean('Hi');
console.log(a); // true
console.log(typeof(a)); // booleanThe Boolean is also a wrapper object of the boolean primitive type. It means that when you pass either true or false to the Boolean constructor, it’ll create a Boolean object.
let b = new Boolean(false);| Operator | boolean | Boolean |
|---|---|---|
typeof | boolean | object |
instanceof Boolean | false | true |
Do comment if you have any doubts or suggestions on this JS boolean topic.
Note: The All JS Examples codes are tested on the Firefox browser and the Chrome browser.
OS: Windows 10
Code: HTML 5 Version
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