JSFiddle - React, Tailwind, and code Playground

by Graham Fairweather

JavaScript

function isStringNumericalInteger(testValue) {
    return typeof testValue === "string" && /^[\-+]?[1-9]{1}\d+$|^[\-+]?0$/.test(testValue);
}

console.log(isStringNumericalInteger("9007199254740991"));
console.log(isStringNumericalInteger("-123216848516878975616587987846516879844651654847"));
console.log(isStringNumericalInteger("0"));
console.log(isStringNumericalInteger("-0"));
console.log(isStringNumericalInteger("1.1"));
console.log(isStringNumericalInteger("-1.1"));
console.log(isStringNumericalInteger("1e10"));
console.log(isStringNumericalInteger("010"));
console.log(isStringNumericalInteger("0x9"));
console.log(isStringNumericalInteger(""));
console.log(isStringNumericalInteger(" "));
console.log(isStringNumericalInteger());
console.log(isStringNumericalInteger(null));
console.log(isStringNumericalInteger([]));
console.log(isStringNumericalInteger({}));