substr_count translated to Javascript from php
function substr_count (haystack, needle, offset, length) { // eslint-disable-line camelcase // discuss at: https://locutus.io/php/substr_count/ // original by: Kevin van Zonneveld (https://kvz.io) // bugfixed by: Onno Marsman (https://twitter.com/onnomarsman) // improved by: Brett Zamir (https://brett-zamir.me) // improved by: Thomas // example 1: substr_count('Kevin van Zonneveld', 'e') // returns 1: 3 // example 2: substr_count('Kevin van Zonneveld', 'K', 1) // returns 2: 0 // example 3: substr_count('Kevin van Zonneveld', 'Z', 0, 10) // returns 3: false var cnt = 0 haystack += '' needle += '' if (isNaN(offset)) { offset = 0 } if (isNaN(length)) { length = 0 } if (needle.length === 0) { return false } offset-- while ((offset = haystack.indexOf(needle, offset + 1)) !== -1) { if (length > 0 && (offset + needle.length) > length) { return false } cnt++ } return cnt}Check out Locutus's Translation Of Php's substr_count function