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EntityKey Class

Provides a durable reference to an object that is an instance of an entity type.

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

'Declaration
<SerializableAttribute> _
<DataContractAttribute(IsReference := True)> _
Public NotInheritable Class EntityKey _
	Implements IEquatable(Of EntityKey)
'Usage
Dim instance As EntityKey

The EntityKey objects are immutable; that is, after they are constructed they cannot be modified.

For more information, see Working with Entity Keys (Entity Framework).

These examples are based on the Adventure Works Sales Model. The examples show you how to create and use an EntityKey.

Using advWorksContext As New AdventureWorksEntities
    Try 
        Dim entity As Object = Nothing 
        Dim entityKeyValues As IEnumerable(Of KeyValuePair(Of String, Object)) = _
                New KeyValuePair(Of String, Object)() { _
                    New KeyValuePair(Of String, Object)("SalesOrderID", 43680)}

        ' Create the  key for a specific SalesOrderHeader object.  
        Dim key As New EntityKey("AdventureWorksEntities.SalesOrderHeader", entityKeyValues)

        ' Try to get the object from the context or the persisted store by its key. 
        If advWorksContext.TryGetObjectByKey(key, entity) Then
            Console.WriteLine("The requested " & entity.GetType().FullName & _
                    " object was found")
        Else
            Console.WriteLine("An object with this key " & _
                    "could not be found.")
        End If 
    Catch ex As EntitySqlException
        Console.WriteLine(ex.ToString)
    End Try 
End Using

System.Object
  System.Data.EntityKey

Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.

Windows 7, Windows Vista, Windows XP SP2, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003

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

.NET Framework

Supported in: 3.5 SP1

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