base64url method
Validates that the string is a valid URL-safe base64 encoded string
(uses - and _ instead of + and /).
message is the error string shown when validation fails.
Returns this to allow method chaining.
Implementation
Field<String> base64url({String message = '', bool exposed = false}) {
return addValidator(
message,
(val) => val != null && val.isNotEmpty && !_base64urlRegex.hasMatch(val),
exposedMessage: exposed,
);
}