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Check if Boolean is true or false in JavaScript

To check if a boolean value is true or false in JavaScript, you can use the typeof operator to check the data type of the value. Here's an example:

Check if Boolean is true or false in JavaScript Examples

In this example, we are defining two variables, isTrue and isFalse, and assigning them the values true and false, respectively. We are then using the typeof operator to check the data type of each value. If the value is a boolean, then it is either true or false.

const isTrue = true;
const isFalse = false;

console.log(typeof isTrue);  // Output: boolean
console.log(typeof isFalse);  // Output: boolean

Here's an example of the output you might see from this code:

boolean
boolean

This indicates that both isTrue and isFalse are boolean values.

Another way to check if a boolean value is true or false is to use the Boolean() function, like this:

In this example, we are using the Boolean() function to convert the isTrue and isFalse values to booleans. If the value is already a boolean, then it will be returned as-is. Otherwise, it will be converted to a boolean.

const isTrue = true;
const isFalse = false;

console.log(Boolean(isTrue));  // Output: true
console.log(Boolean(isFalse));  // Output: false

The output of this code would be the same as the previous example:

true
false

which indicates that isTrue is true and isFalse is false.

Check if Boolean is true or false using if Condition Example

To check if a boolean value is true or false using an if condition in JavaScript, you can simply compare the value to the true and false keywords, like this:

In this example, we are defining two variables, isTrue and isFalse, and assigning them the values true and false, respectively. We are then using the if statement to compare each value to the true and false keywords. If the value matches, then the corresponding message is logged to the console.

const isTrue = true;
const isFalse = false;

if (isTrue === true) {
  console.log('isTrue is true');
}

if (isFalse === false) {
  console.log('isFalse is false');
}

Here's an example of the output you might see from this code:

isTrue is true
isFalse is false

This indicates that isTrue is true and isFalse is false.

Another way to check if a boolean value is true or false using an if condition is to use the Boolean() function, like this:

In this example, we are using the Boolean() function to convert the isTrue and isFalse values to booleans. If the value is already a boolean, then it will be returned as-is. Otherwise, it will be converted to a boolean. We are then using the if statement to check the boolean value and log a message if the condition is satisfied.

const isTrue = true;
const isFalse = false;

if (Boolean(isTrue)) {
  console.log('isTrue is true');
}

if (!Boolean(isFalse)) {
  console.log('isFalse is false');
}

The output of this code would be the same as the previous example:

isTrue is true
isFalse is false

which indicates that isTrue is true and isFalse is false.

Check if Boolean is true or false using switch case Statement Example

To check if a boolean value is true or false using a case statement in JavaScript, you can use the switch statement and compare the value to the true and false keywords, like this:

In this example, we are defining two variables, isTrue and isFalse, and assigning them the values true and false, respectively. We are then using the switch statement to compare each value to the true and false keywords. If the value matches, then the corresponding message is logged to the console.

const isTrue = true;
const isFalse = false;

switch (isTrue) {
  case true:
    console.log('isTrue is true');
    break;
  default:
    console.log('isTrue is not true');
    break;
}

switch (isFalse) {
  case false:
    console.log('isFalse is false');
    break;
  default:
    console.log('isFalse is not false');
    break;
}

Here's an example of the output you might see from this code:

isTrue is true
isFalse is false

This indicates that isTrue is true and isFalse is false.

Another way to check if a boolean value is true or false using a case statement is to use the Boolean() function, like this:

In this example, we are defining two variables, isTrue and isFalse, and assigning them the values true and false, respectively. We are then using the Boolean() function to convert each value to a boolean. We are then using the switch statement to compare the boolean value to the true and false keywords. If the value matches, then the corresponding message is logged to the console.

const isTrue = true;
const isFalse = false;

switch (Boolean(isTrue)) {
  case true:
    console.log('isTrue is true');
    break;
  default:
    console.log('isTrue is not true');
    break;
}

switch (Boolean(isFalse)) {
  case false:
    console.log('isFalse is false');
    break;
  default:
    console.log('isFalse is not false');
    break;
}

Here's an example of the output you might see from this code:

isTrue is true
isFalse is false

This indicates that isTrue is true and isFalse is false.

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