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ObjectStateEntry.GetModifiedProperties Method

Returns the names of an object's properties that have changed since the last time SaveChanges was called.

Namespace:  System.Data.Objects
Assembly:  System.Data.Entity (in System.Data.Entity.dll)

public abstract IEnumerable<string> GetModifiedProperties()

Return Value

Type: System.Collections.Generic.IEnumerable<String>
An IEnumerable<T> collection of names as String.

Returns the property names that are marked Modified.

The example in this topic is based on the Adventure Works Sales Model. The 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.


int orderId = 43680;

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

    // Get ObjectStateEntry from EntityKey.
    ObjectStateEntry stateEntry =
        context.ObjectStateManager
        .GetObjectStateEntry(((IEntityWithKey)order).EntityKey);

    //Get the current value of SalesOrderHeader.PurchaseOrderNumber.
    CurrentValueRecord rec1 = stateEntry.CurrentValues;
    string oldPurchaseOrderNumber =
        (string)rec1.GetValue(rec1.GetOrdinal("PurchaseOrderNumber"));

    //Change the value.
    order.PurchaseOrderNumber = "12345";
    string newPurchaseOrderNumber =
        (string)rec1.GetValue(rec1.GetOrdinal("PurchaseOrderNumber"));

    // Get the modified properties.
    IEnumerable<string> modifiedFields = stateEntry.GetModifiedProperties();
    foreach (string s in modifiedFields)
        Console.WriteLine("Modified field name: {0}\n Old Value: {1}\n New Value: {2}",
            s, oldPurchaseOrderNumber, newPurchaseOrderNumber);

    // Get the Entity that is associated with this ObjectStateEntry.
    SalesOrderHeader associatedEnity = (SalesOrderHeader)stateEntry.Entity;
    Console.WriteLine("Associated Enity's ID: {0}", associatedEnity.SalesOrderID);
}


.NET Framework

Supported in: 4, 3.5 SP1

.NET Framework Client Profile

Supported in: 4

Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

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