extension StringConverter on String { bool isEmailValid() { RegExp regex = RegExp( r"[a-z0-9!#$%&'*+/=?^_`{|}~-]+(?:\.[a-z0-9!#$%&'*+/=?^_`{|}~-]+)*@(?:[a-z0-9](?:[a-z0-9-]*[a-z0-9])?\.)+[a-z0-9](?:[a-z0-9-]*[a-z0-9])?"); if (regex.hasMatch(this)) { return true; } else { return false; } } String formatToIdnPhone() { if (startsWith("0")) { String phoneNumber = replaceFirst("0", "+62"); return phoneNumber; } return "+${trim()}"; } }