hasLengthFn method
FieldValidator<String?, String?>
hasLengthFn(
- ValueGetter<
int> length, [ - MessageCallBack<
String> ? message
check is the value has length of length
Implementation
FieldValidator<String?, String?> hasLengthFn(ValueGetter<int> length,
[MessageCallBack<String>? message]) {
return next((messages, value) {
var len = length();
if (value != null && value.length != len) {
return message?.call(messages, value) ?? messages.hasLength(len);
}
return null;
});
}