mask method

String mask(
  1. int visibleLength, {
  2. String maskChar = '*',
})

Masks part of a string (e.g., credit card or password). Example: "12345678".mask(4) → "****5678"

Implementation

String mask(int visibleLength, {String maskChar = '*'}) {
  if (length <= visibleLength) return this;
  return maskChar * (length - visibleLength) +
      substring(length - visibleLength);
}