using System; using System.Collections.Generic; using System.Globalization; using System.Linq; using System.Text; using System.Threading.Tasks; using System.Windows.Controls; namespace Tango.MachineStudio.Statistics.ValidationRules { public class DateExpiredRule : ValidationRule { public override ValidationResult Validate(object value, CultureInfo cultureInfo) { DateTime orderDate = (DateTime)value; return new ValidationResult(orderDate < DateTime.Now, "Please enter a date until today."); } } }