JavaScript: Return true if the specified value is null, false otherwise

JavaScript fundamental (ES6 Syntax): Exercise-196 with Solution

Check If Null

Write a JavaScript program that will return true if the specified value is null, false otherwise.

• Use the strict equality operator to check if the value of val is equal to null.

Sample Solution:

JavaScript Code:

// Define a function 'isNull' that checks if the given value 'val' is null
const isNull = val =>
  // Check if 'val' is strictly equal to null
  val === null;

// Test cases to check if the values are null
console.log(isNull(null)); // true (the value is null)
console.log(isNull(123));  // false (the value is not null)

Output:

true
false

Visual Presentation:

Flowchart:

Live Demo:

See the Pen javascript-basic-exercise-196-1 by w3resource (@w3resource) on CodePen.

For more Practice: Solve these Related Problems:

• Write a JavaScript program that returns true if a given value is exactly null.
• Write a JavaScript function that distinguishes between null and undefined in its type check.
• Write a JavaScript program that checks a variable and logs whether it is null, undefined, or neither.
• Write a JavaScript function that returns a custom message if a value is null.

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