checkPassword function

String? checkPassword(
  1. String? input
)

Implementation

String? checkPassword(String? input){
  if(input==null)return "Please enter Password";
  if (!RegExp(password12Pattern).hasMatch(input)) {
    return "Password must be at least 12 characters";}
  if (!input.contains(RegExp(r'[a-z]'))){
    return "Password must contain a lower case letter";}
  if (!input.contains(RegExp(r'[A-Z]'))){
    return "Password must contain a upper case letter";}
  if (!input.contains(RegExp(r'[0-9]'))){
    return "Password must contain a number";}
  if (!input.contains(RegExp(r'[!@#\$%^&*~(),.?":{}|<>]'))){
    return "Password must contain a special letter";}
  return null;
}