How to Check if a Variable is an Integer in JavaScript

0
33
How to Filter an Object by Key in JavaScript


Jan 13, 2022

To check if a variable is an integer in JavaScript, use Number.isInteger().
Number.isInteger() returns true or false depending on the parameter provided.

let example = 12.1;
Number.isInteger(example); 
example = 12;
Number.isInteger(example); 
example = Infinity;
Number.isInteger(example); 

Non-numeric values will return false, even if the value is an instance of the Number class.

Number.isInteger(null); 
Number.isInteger('42'); 
Number.isInteger(new Number(5)); 

Remember that JavaScript can only represent up to 16 decimal places, so Number.isInteger() may return surprising results in cases where JavaScript doesn’t have sufficient numeric precision to represent the output.

let example = 5 + 1e-16;
Number.isInteger(example); 

example = 5 + 5e-16;
Number.isInteger(example); 

More Fundamentals Tutorials



Source link

Leave a reply

Please enter your comment!
Please enter your name here