Database Reference
In-Depth Information
Listing 12-7.
Overriding the SaveChanges Event to Set the Default Values
class Program
{
static void Main(string[] args)
{
RunExample();
}
static void RunExample()
{
using (var context = new EFRecipesEntities())
{
context.PurchaseOrders.Add(
new PurchaseOrder { Amount = 109.98M });
context.PurchaseOrders.Add(
new PurchaseOrder { Amount = 20.99M });
context.PurchaseOrders.Add(
new PurchaseOrder { Amount = 208.89M });
context.SaveChanges();
}
using (var context = new EFRecipesEntities())
{
Console.WriteLine("Purchase Orders");
foreach (var po in context.PurchaseOrders)
{
Console.WriteLine("Purchase Order: {0}",
po.PurchaseOrderId.ToString(""));
Console.WriteLine("\tPaid: {0}", po.Paid ? "Yes" : "No");
Console.WriteLine("\tAmount: {0}", po.Amount.ToString("C"));
Console.WriteLine("\tCreated On: {0}",
po.CreateDate.ToShortTimeString());
Console.WriteLine("\tModified at: {0}",
po.ModifiedDate.ToShortTimeString());
}
}
}
}
public partial class EFRecipesEntities
{
public override int SaveChanges()
{
var changeSet = this.ChangeTracker.Entries().Where(e => e.Entity is PurchaseOrder);
if (changeSet != null)
{
foreach (var order in changeSet.Where(c => c.State == System.Data.Entity.
EntityState.Added).Select(a => a.Entity as PurchaseOrder))
