TransferLog.cs #2

using System.ComponentModel;
using System.ComponentModel.DataAnnotations;
using System.Web.DynamicData;
using System;
using System.Linq;
using Aspnet.Samples.DynamicData;

namespace TicketCenter_Data
{
    //  Attach the TransferLogMetadata to the TransferLog class
    [MetadataType(typeof(TransferLogMetadata))]
    [Security(Role = "Users", Action = "Details")]
    [Security(Role = "Users", Action = "Edit")]
    [Security(Role = "Users", Action = "Insert")]
    [Security(Role = "Users", Action = "List")]
    public partial class TransferLog
    {
        partial void OnValidate(System.Data.Linq.ChangeAction action)
        {
            if (action == System.Data.Linq.ChangeAction.Insert || action == System.Data.Linq.ChangeAction.Update)
            {
                var dc = new ITCDataContext();
                var q1 = dc.TicketsAllocations.SingleOrDefault(c => c.JKID == this.JKIDFrom && c.EventID == this.EventID);
                q1.TicketsIssued -= this.QtyTransfer;
                if (q1.TicketsIssued >= 0)
                {
                    dc.SubmitChanges();
                }
                else
                {
                    throw new ValidationException("Can only transfer " + (this.QtyTransfer + q1.TicketsIssued) + " tickets.");
                }

                var q2 = dc.TicketsAllocations.SingleOrDefault(c => c.JKID == this.JKIDTo && c.EventID == this.EventID);
                q2.TicketsIssued += this.QtyTransfer;
                dc.SubmitChanges();

                Modified = DateTime.Now;  //Update the Timestamp in Table TransferLog
            }
        }
    }

    [TableName("Transfer In Out")]
    public class TransferLogMetadata
    {
        [DisplayName("Transfer Date")]
        [DefaultValue("mm-dd-yyyy")]
        [DisplayFormat(DataFormatString = "{0:MM-dd-yyyy}")]
        public object DateTransfer { get; set; }

        [DisplayName("Quantity")]
        public object QtyTransfer { get; set; }

        [DisplayName("From JK")]
        public object JK { get; set; }

        [DisplayName("To JK")]
        public object JK1 { get; set; }


        //  Columns I want hidden
        [ScaffoldColumn(false)]
        public object Modified { get; set; }

    }

}