JavaScript: Check whether a value is an integer or not

Last update on August 19 2022 21:50:50 (UTC/GMT +8 hours)

JavaScript Math: Exercise-15 with Solution

Write a JavaScript function to check whether a value is an integer or not.

Test Data:
console.log(is_Int(23));
console.log(is_Int(4e2));
console.log(is_Int(NaN));
console.log(is_Int(23.75));
console.log(is_Int(-23));
Output :
true
true
false
false
true

Pictorial Presentation:

$JavaScript: Math - Check whether a value is an integer or not.$

Sample Solution:-

HTML Code:

<!DOCTYPE html>
  <html>
  <head>
  <meta charset="utf-8">
  <title>Check whether a value is an integer or not</title>
  </head>
  <body>
</body>
  </html>

JavaScript Code:

function is_Int(num) {
  
   if (typeof num !== 'number')
       return false; 
  
  return !isNaN(num) && 
         parseInt(Number(num)) == num && 
         !isNaN(parseInt(num, 10));
}
console.log(is_Int(23));
console.log(is_Int(4e2));
console.log(is_Int(NaN));
console.log(is_Int(23.75));
console.log(is_Int(-23));

Sample Output:

true
true
false
false
true

Flowchart:

$Flowchart: JavaScript Math- Check whether a value is an integer or not$

Live Demo:

See the Pen javascript-math-exercise-15 by w3resource (@w3resource) on CodePen.

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