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

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

I have used Entity Framework with ObjectDataSource for GridView. while i have tried with updatemethod i got the run time error message

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

Here is my aspx file code:

    <asp:ObjectDataSource ID="odsCustomerList" runat="server" DataObjectTypeName="EF.POCO.Customer"
                TypeName="EF.BusinessLayer.CustomerMaster" SelectMethod="ReadAllCustomer" SortParameterName="sortExpression"
                ConflictDetection="CompareAllValues" OldValuesParameterFormatString="orig{0}"  
                UpdateMethod="UpdateCustomer" DeleteMethod="DeleteCustomer">
    </asp:ObjectDataSource>

Here is my Code File of DA Layer

     public void UpdateCustomer(Customer customer, Customer origCustomer)
    {
        try
        {

            BusinessEntityBase.Entities.Customers.MergeOption = System.Data.Objects.MergeOption.NoTracking;
            BusinessEntityBase.Entities.Customers.Attach(origCustomer);
            BusinessEntityBase.Entities.ApplyCurrentValues("Customer", customer);
            BusinessEntityBase.Entities.SaveChanges();
        }
        catch (Exception ex)
        {
            throw ex;
        }
    }

Is there anyone who can help to sort out this issue ?

Absolute dupe, including the **exact** wording of the question title. Please search first before posting; this gets you answers more quickly and reduces the clutter here (as well as not wasting the time of people who do research it and find the duplicates in order to do so). Thanks. — Ken White, Jul 01 '11 at 00:32

score 1 · Accepted Answer · answered Jun 30 '11 at 13:05

How are you managing the context (ObjectContext) - does BusinessEntityBase.Entities is shared across multiple requests? This can be an issue - because object retrieved from one request can conflict when you are trying to update the object from other request (and so attach will fail). See this link for possible solution: http://dotnetslackers.com/articles/ado_net/Managing-Entity-Framework-ObjectContext-lifespan-and-scope-in-n-layered-ASP-NET-applications.aspx

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

1 Answers1