isBirthday method
Get a statement to check weather now has same day and month of this value.
Implementation
ConditionQuery isBirthday() {
var now = DateTimeStringField.now;
var result = ConditionQuery();
result.queryBuilder =
() => (day.equals(now.day) & month.equals(now.month)).buildQuery();
result.parametersBuilder = () => getParameters();
return result;
}