Detach Entity Collection

Question

Well, i have a Model with a collection saving changes in a loop structure

foreach(Customer objCustomer in listCustomer)
{
    try
    {
        db.Customer.Add(objCustomer);
        db.SaveChanges();
    }
    catch(Exception ex)
    {
        db.Entry(objCustomer).State = EntityState.Detach;
    }
}

When it throws me any exception in a collection related to entity, the next ones keeps throwing exceptions.

I tried to detach the entire collection but it didn't work

foreach(Customer objCustomer in listCustomer)
{
    try
    {
        db.Customer.Add(objCustomer);
        db.SaveChanges();
    }
    catch(Exception ex)
    {
        for (int i = 0; i < objCustomer.Address; i++)
        {
            db.Entry(objCustomer.Address[i]).State = EntityState.Detach;
        }
        db.Entry(objCustomer).State = EntityState.Detach;
    }
}

Any suggestion?

1. I don't think you can "detach" the entity if the "add" operation failed. 2. I'm guessing that you are actually trying to update an existing customer but are incorrectly adding it to the database? — failedprogramming, Mar 12 '14 at 01:09
DbValidation exception in collection Address, after the first it keeps throwing the same exception for all entities — Teta, Mar 12 '14 at 15:20

score 1 · Accepted Answer · edited May 23 '17 at 10:25

1

I don't know why but it works, i used like it refers in this post

EntityCollection Clear() and Remove() methods

objCustomer.Address.ToList().ForEach(x => db.Entry(x).State = EntityState.Detached);

It is almost as i did before using "for"

Thanks anyway everyone

edited May 23 '17 at 10:25

Community

1
1

answered Mar 12 '14 at 18:15

Teta

129
9

score 0 · Answer 2 · answered Mar 12 '14 at 01:22

0

i thought that the exception of second code maybe has been never occurred?

In addition，your code has any transaction ?

answered Mar 12 '14 at 01:22

lixincun

1

I imagine that the transaction open when i use using (Context db = new Context){} – Teta Mar 12 '14 at 01:30

score 0 · Answer 3 · answered Mar 12 '14 at 01:38

0

Try this? Warning not tested!

using(var db = new Context())
{

    foreach(Customer objCustomer in listCustomer)
    {
         var exists = db.Customer.FirstOrDefault(x => x.CustomerID == objCustomer.CustomerID;

         if( exists = null)
         {
            db.Customer.Add(objCustomer);

         }
         else
         {
            db.Entry(objCustomer).State = EntityState.Modified;
         }
         db.SaveChanges();

    }

}

answered Mar 12 '14 at 01:38

failedprogramming

2,532
18
21

It did not work "The ObjectStateManager cannot track multiple objects with the same key" – Teta Mar 12 '14 at 15:19

Detach Entity Collection

3 Answers3