Why ModelState manager does not let me delete a record?

Question

first of all happy new year to all !!!!

i have following code to remove a record from the db table tr_shoppingCart

 tr_ShoppingCart cart = new tr_ShoppingCart
                        {
                            cartId = sc.CartId,
                            CartGenDt = sc.CreateTime,
                            UserId = ((SessionData)Session["object"]).sessObj.UserId,
                            prodId = obj.prodId,
                            Qnty = obj.Qnty,
                            Total = obj.Total
                        };


                        if (ModelState.IsValid)
                        {
                            //db.Entry(cart).State = System.Data.EntityState.Deleted;
                            db.tr_ShoppingCart.Attach(cart);
                            db.tr_ShoppingCart.Remove(cart);
                            db.SaveChanges();
                        }

but it has given the error:

An object with the same key already exists in the ObjectStateManager. The ObjectStateManager cannot track multiple objects with the same key.

here is my DB table tr_ShoppingCart

score 0 · Answer 1 · edited May 23 '17 at 12:04

0

This question is explained in more detail here. I assume that cartId is your key. Check that sc.CartId is not already in tr_ShoppingCart list. If it is, than you must ensure that you generate your ids correctly.

edited May 23 '17 at 12:04

Community

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answered Jan 01 '16 at 09:47

Alexei - check Codidact

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in the db tables tr_ShoppingCart cartId and ProdId was set as PKs where CartID is a GUID generated in the client. – Phill Greggan Jan 01 '16 at 11:28
1

Try this before attaching: var theCart = db.tr_ShoppingCart.Where(c => c.cartId == sc.CartId && c.prodId == obj.prodId); and check if theCart has items. – Alexei - check Codidact Jan 01 '16 at 12:27
i want to delete that product from the cart that was the whole idea, how to do it? – Phill Greggan Jan 01 '16 at 13:46
even more, when i comment the attach() and uncomment remove() its says The object cannot be deleted because it was not found in the ObjectStateManager – Phill Greggan Jan 01 '16 at 14:02

Why ModelState manager does not let me delete a record?

1 Answers1