How to add & update within entity framework - entity-framework

Question

my Model Entity FrameWork :
public partial class T02
{
public long ID { get; set; }
public int F01 { get; set; }
}
Table : T02
------------------------
id[Key,identity] F01
------------------------
1 a
2 b
====================================================
i have a button > Code
public void Button_Click(object Sender, EventArgs e)
{
T02 T1 = new T02 { ID = 1, F01 = "x" };
T02 T2 = new T02 { ID = 2, F01 = "y" };
T02 T3 = new T02 { ID = 0, F01 = "g" };
T02 T4 = new T02 { ID = 0, F01 = "h" };
// How ID > 1 2 Update in Table &
// because not in table, > g , h > automatic add to Table
// ???
}
my problem is : i not ontime update and if T02.ID not on the table automatic added..
Is it possible that I do added to table Records Without id and i do Update Records With id
i worked c#.NET 4.5 . Thanks

Answer 1

Add this method to your Context class:
protected virtual void InsertOrUpdate<T>(T entity, long id)
{
if (id == default(int))
this.Set<T>().Add(entity);
else
this.Entry(entity).State = EntityState.Modified;
}
Which can be used something like this:
public void Button_Click(object Sender, EventArgs e)
{
T02 T1 = new T02 { ID = 1, F01 = "x" };
T02 T2 = new T02 { ID = 2, F01 = "y" };
T02 T3 = new T02 { ID = 0, F01 = "g" };
T02 T4 = new T02 { ID = 0, F01 = "h" };
using(var context = new MyDbContext())
{
context.InsertOrUpdate(T1, T1.ID);
context.InsertOrUpdate(T2, T2.ID);
context.InsertOrUpdate(T3, T3.ID);
context.InsertOrUpdate(T4, T4.ID);
}
}
Once this is working you can consider implementing a standard interface across all of your POCO classes that exposes the ID property so that you no longer have to pass ID into the method:
public interface IId
{
long ID { get; }
}
public partial class T02 : IId
{
public long ID { get; set; }
public int F01 { get; set; }
}
which gives you a neater method in your Context
protected virtual void InsertOrUpdate<T>(T entity) where T : IId
{
if (entity.ID == default(int))
this.Set<T>().Add(entity);
else
this.Entry(entity).State = EntityState.Modified;
}