覆盖Entity Framework 5中的SaveChanges(Override SaveChanges in Entity Framework 5)

 使用C＃，我使用“从数据库生成”生成了我的数据库模型。 使用T4模板生成POCO类和上下文。 一切正常，应用程序可以编辑，插入等，除了我不能覆盖我的实体类中的SaveChanges方法。 我需要这样做来添加商业逻辑。 这是上下文类： 
 
//------------------------------------------------------------------------------
// <auto-generated>
//    This code was generated from a template.
//
//    Manual changes to this file may cause unexpected behavior in your application.
//    Manual changes to this file will be overwritten if the code is regenerated.
// </auto-generated>
//------------------------------------------------------------------------------

namespace WebApplication1
{
    using System;
    using System.Data.Entity;
    using System.Data.Entity.Infrastructure;

   public partial class IInvoiceEntities2 : DbContext
   {
        public IInvoiceEntities2 ()
            : base("name=IInvoiceEntities2 ")
        {
        }        


    protected override void OnModelCreating(DbModelBuilder modelBuilder)
    {
        throw new UnintentionalCodeFirstException();
    }






    public DbSet<Company> Companies { get; set; }
    public DbSet<CompanyDetail> CompanyDetails { get; set; }
    public DbSet<CompanyVersion> CompanyVersions { get; set; }
    public DbSet<CustomerDetail> CustomerDetails { get; set; }
    }
}
 
 当我在其中设置断点并编辑实体时，我的SaveChanges方法没有被击中的任何想法？ 
 
 更新： 
 
 我现在覆盖上下文类中的ValidateEntity方法以及SaveChanges，但是当我编辑实体并在SaveChanges或ValidateEntity中设置断点时，两个方法都没有被调用（参见上面的代码） 
 
 更新2： 
 
 我现在已经在App_Code文件夹中为SaveChanges和ValidateEntity创建了一个部分类，但是这些方法仍然没有被执行： 
 
namespace WebApplication1
{
using System;
using System.Data.Entity;
using System.Data.Entity.Infrastructure;

public partial class IInvoiceEntities2 : DbContext
{
    public IInvoiceEntities2 ()
        : base("name=IInvoiceEntities2 ")
    {
    }


    public override int SaveChanges()
    {
        return base.SaveChanges();
    }




protected override DbEntityValidationResult ValidateEntity(
System.Data.Entity.Infrastructure.DbEntityEntry entityEntry,
IDictionary<object, object> items)
{
  // do stuff

    if (result.ValidationErrors.Count > 0)
    {
        return result;
    }
    else
    {
        return base.ValidateEntity(entityEntry, items);
    }
}





}
 
 } 

Using C#, I've generated my DB model using "Generate from Database". The POCO classes and context are generated with T4 templates. everything is working fine and the app is able to edit, insert etc. except I cannot override the SaveChanges method in my entities class. I need to do this to add buisiness logic. Here is the context class:
 
//------------------------------------------------------------------------------
// <auto-generated>
//    This code was generated from a template.
//
//    Manual changes to this file may cause unexpected behavior in your application.
//    Manual changes to this file will be overwritten if the code is regenerated.
// </auto-generated>
//------------------------------------------------------------------------------

namespace WebApplication1
{
    using System;
    using System.Data.Entity;
    using System.Data.Entity.Infrastructure;

   public partial class IInvoiceEntities2 : DbContext
   {
        public IInvoiceEntities2 ()
            : base("name=IInvoiceEntities2 ")
        {
        }        


    protected override void OnModelCreating(DbModelBuilder modelBuilder)
    {
        throw new UnintentionalCodeFirstException();
    }






    public DbSet<Company> Companies { get; set; }
    public DbSet<CompanyDetail> CompanyDetails { get; set; }
    public DbSet<CompanyVersion> CompanyVersions { get; set; }
    public DbSet<CustomerDetail> CustomerDetails { get; set; }
    }
}
 
Any ideas why my SaveChanges method isn't being hit when I set a breakpoint in it and edit an entity?
 
Update:
 
I now override the ValidateEntity method in my context class as well as SaveChanges, but when I edit an entity and set a breakpoint in SaveChanges or ValidateEntity, neither methods are being called (see code above)
 
Update 2:
 
I've now created a partial class in App_Code folder for the SaveChanges and ValidateEntity, but these methods are still not being executed :
 
namespace WebApplication1
{
using System;
using System.Data.Entity;
using System.Data.Entity.Infrastructure;

public partial class IInvoiceEntities2 : DbContext
{
    public IInvoiceEntities2 ()
        : base("name=IInvoiceEntities2 ")
    {
    }


    public override int SaveChanges()
    {
        return base.SaveChanges();
    }




protected override DbEntityValidationResult ValidateEntity(
System.Data.Entity.Infrastructure.DbEntityEntry entityEntry,
IDictionary<object, object> items)
{
  // do stuff

    if (result.ValidationErrors.Count > 0)
    {
        return result;
    }
    else
    {
        return base.ValidateEntity(entityEntry, items);
    }
}





}
 
}

原文：https://stackoverflow.com/questions/27237672