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ObjectStateManager.GetObjectStateEntry Method

Definition

Returns an ObjectStateEntry for a specific object or relationship entry.

Overloads

GetObjectStateEntry(EntityKey)

Returns an ObjectStateEntry for the object or relationship entry with the specified key.

GetObjectStateEntry(Object)

Returns an ObjectStateEntry for the specified object.

GetObjectStateEntry(EntityKey)

Returns an ObjectStateEntry for the object or relationship entry with the specified key.

public:
 System::Data::Objects::ObjectStateEntry ^ GetObjectStateEntry(System::Data::EntityKey ^ key);
public System.Data.Objects.ObjectStateEntry GetObjectStateEntry (System.Data.EntityKey key);
member this.GetObjectStateEntry : System.Data.EntityKey -> System.Data.Objects.ObjectStateEntry
Public Function GetObjectStateEntry (key As EntityKey) As ObjectStateEntry

Parameters

key
EntityKey

The EntityKey.

Returns

The corresponding ObjectStateEntry for the given EntityKey.

Exceptions

When key is null.

When the specified key cannot be found in the state manager.

No entity with the specified EntityKey exists in the ObjectStateManager.

Examples

This example gets the ObjectStateEntry for the given EntityKey from the ObjectStateManager. Then it gets the current value of the SalesOrderHeader.PurchaseOrderNumber property, changes the property's value, and enumerates through the collection of modified properties.

// Specify the order to update.
int orderId = 43680;

using (AdventureWorksEntities context =
    new AdventureWorksEntities())
{
    try
    {
        var order = (from o in context.SalesOrderHeaders
                     where o.SalesOrderID == orderId
                     select o).First();

        // Change the status of an existing order.
        order.Status = 1;

        // Delete the first item in the order.
        context.DeleteObject(order.SalesOrderDetails.First());

        // Create a new SalesOrderDetail object.
        // You can use the static CreateObjectName method (the Entity Framework
        // adds this method to the generated entity types) instead of the new operator:
        // SalesOrderDetail.CreateSalesOrderDetail(1, 0, 2, 750, 1, (decimal)2171.2942, 0, 0,
        //                                         Guid.NewGuid(), DateTime.Today));
        SalesOrderDetail detail = new SalesOrderDetail
        {
            SalesOrderID = 0,
            SalesOrderDetailID = 0,
            OrderQty = 2,
            ProductID = 750,
            SpecialOfferID = 1,
            UnitPrice = (decimal)2171.2942,
            UnitPriceDiscount = 0,
            LineTotal = 0,
            rowguid = Guid.NewGuid(),
            ModifiedDate = DateTime.Now
        };
        order.SalesOrderDetails.Add(detail);

        // Get the ObjectStateEntry for the order.
        ObjectStateEntry stateEntry =
            context.ObjectStateManager
            .GetObjectStateEntry(order);
        Console.WriteLine("State before SaveChanges() is called: {0}",
            stateEntry.State.ToString());

        // Save changes in the object context to the database.
        int changes = context.SaveChanges();

        Console.WriteLine("State after SaveChanges() is called: {0}",
            stateEntry.State.ToString());

        Console.WriteLine(changes.ToString() + " changes saved!");
        Console.WriteLine("Updated item for order ID: "
            + order.SalesOrderID.ToString());

        // Iterate through the collection of SalesOrderDetail items.
        foreach (SalesOrderDetail item in order.SalesOrderDetails)
        {
            Console.WriteLine("Item ID: "
                + item.SalesOrderDetailID.ToString() + "  Product: "
                + item.ProductID.ToString() + "  Quantity: "
                + item.OrderQty.ToString());
        }
    }
    catch (UpdateException ex)
    {
        Console.WriteLine(ex.ToString());
    }
}

Remarks

Use the TryGetObjectStateEntry(EntityKey, ObjectStateEntry) method to return an ObjectStateEntry object without having to handle the InvalidOperationException raised by the GetObjectStateEntry(EntityKey) method.

Applies to

GetObjectStateEntry(Object)

Returns an ObjectStateEntry for the specified object.

public:
 System::Data::Objects::ObjectStateEntry ^ GetObjectStateEntry(System::Object ^ entity);
public System.Data.Objects.ObjectStateEntry GetObjectStateEntry (object entity);
member this.GetObjectStateEntry : obj -> System.Data.Objects.ObjectStateEntry
Public Function GetObjectStateEntry (entity As Object) As ObjectStateEntry

Parameters

entity
Object

The Object to which the retrieved ObjectStateEntry belongs.

Returns

The corresponding ObjectStateEntry for the given Object.

Exceptions

No entity for the specified Object exists in the ObjectStateManager.

Remarks

Use the TryGetObjectStateEntry(Object, ObjectStateEntry) method to return an ObjectStateEntry object without having to handle the InvalidOperationException raised by the GetObjectStateEntry(Object) method.

Applies to