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Javascript - Is Finite and Valid Number

Check if a number is valid and finite (js code)


programming language: javascript ES5 / ES6 and later
operating system: any
Updated:


Method definition: ES5

// classic function
function isFiniteValidNumber(num) {
	return !! (typeof(num) != 'number') ? false : !! (Number.isFinite(num) && (!Number.isNaN(num)));
}


Method definition: ES6

// arrow function
const isFiniteValidNumber = (num) => {
	return !! (typeof(num) != 'number') ? false : !! (Number.isFinite(num) && (!Number.isNaN(num)));
};


Test case: ES5 or ES6

console.log(isFiniteValidNumber(undefined));
// outputs: false

console.log(isFiniteValidNumber(null));
// outputs: false

console.log(isFiniteValidNumber('abc'));
// outputs: false

console.log(isFiniteValidNumber('1'));
// outputs: false

console.log(isFiniteValidNumber(1/0));
// outputs: false

console.log(isFiniteValidNumber(1));
// outputs: true

console.log(isFiniteValidNumber(1.01));
// outputs: true