Format Phone Number using JavaScript

formatNumber.js

function formatNumber(number, format = 'xxx-xxx-xxx') {
	let result = '',
		curIndex = 0;
	
	format.split('').forEach(char => {
		if(char.toLowerCase() === 'x') {
			result += number.charAt(curIndex)
			curIndex++
		} else {
			result += char
		}
    })

	return result
}

console.log(formatNumber('9619452263')) // "961-945-226"
console.log(formatNumber('9619452263', 'XX-XX-XX-XX-XX')) // "96-19-45-22-63"