string-kit-js/index.js

[](https://www.npmjs.com/package/string-kit-js) [](https://opensource.org/licenses/MIT)

function isBlank(str) {
  return str === null || str === undefined || (typeof str === "string" && str.trim() === "");
}

function isNotBlank(str) {
  return !isBlank(str);
}

function isEmpty(str) {
  return str === null || str === undefined || str === "";
}

function isNotEmpty(str) {
  return !isEmpty(str);
}

function equals(str1, str2) {
  return str1 === str2;
}

function equalsIgnoreCase(str1, str2) {
  if (str1 == null || str2 == null) return false;
  return String(str1).toLowerCase() === String(str2).toLowerCase();
}

function contains(str, substr) {
  if (str == null || substr == null) return false;
  return String(str).includes(substr);
}

function startsWith(str, prefix) {
  if (str == null || prefix == null) return false;
  return String(str).startsWith(prefix);
}

function endsWith(str, suffix) {
  if (str == null || suffix == null) return false;
  return String(str).endsWith(suffix);
}

function toUpper(str) {
  return str ? String(str).toUpperCase() : "";
}

function toLower(str) {
  return str ? String(str).toLowerCase() : "";
}

function capitalize(str) {
  if (!str) return "";
  return str.charAt(0).toUpperCase() + str.slice(1).toLowerCase();
}

function defaultIfBlank(str, defaultStr) {
  return isBlank(str) ? defaultStr : str;
}

function defaultIfEmpty(str, defaultStr) {
  return isEmpty(str) ? defaultStr : str;
}

function substringBefore(str, separator) {
  if (isEmpty(str) || separator == null) return str;
  const idx = str.indexOf(separator);
  return idx === -1 ? str : str.substring(0, idx);
}

function substringAfter(str, separator) {
  if (isEmpty(str) || separator == null) return "";
  const idx = str.indexOf(separator);
  return idx === -1 ? "" : str.substring(idx + separator.length);
}

module.exports = {
  isBlank,
  isNotBlank,
  isEmpty,
  isNotEmpty,
  equals,
  equalsIgnoreCase,
  contains,
  startsWith,
  endsWith,
  toUpper,
  toLower,
  capitalize,
  defaultIfBlank,
  defaultIfEmpty,
  substringBefore,
  substringAfter
};