Designates a property to represent a database association, such as a foreign key relationship.
Assembly: System.Data.Linq (in System.Data.Linq.dll)
Thetype exposes the following members.
|DeleteOnNull||When placed on a 1:1 association whose foreign key members are all non-nullable, deletes the object when the association is set to null.|
|DeleteRule||Gets or sets delete behavior for an association.|
|IsForeignKey||Gets or sets the member as the foreign key in an association representing a database relationship.|
|IsUnique||Gets or sets the indication of a uniqueness constraint on the foreign key.|
|Name||Gets or sets the name of a column. (Inherited from DataAttribute.)|
|OtherKey||Gets or sets one or more members of the target entity class as key values on the other side of the association.|
|Storage||Gets or sets a private storage field to hold the value from a column. (Inherited from DataAttribute.)|
|ThisKey||Gets or sets members of this entity class to represent the key values on this side of the association.|
|TypeId||When implemented in a derived class, gets a unique identifier for this Attribute. (Inherited from Attribute.)|
|Equals||Infrastructure. Returns a value that indicates whether this instance is equal to a specified object. (Inherited from Attribute.)|
|Finalize||Allows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection. (Inherited from Object.)|
|GetHashCode||Returns the hash code for this instance. (Inherited from Attribute.)|
|GetType||Gets the Type of the current instance. (Inherited from Object.)|
|IsDefaultAttribute||When overridden in a derived class, indicates whether the value of this instance is the default value for the derived class. (Inherited from Attribute.)|
|Match||When overridden in a derived class, returns a value that indicates whether this instance equals a specified object. (Inherited from Attribute.)|
|MemberwiseClone||Creates a shallow copy of the current Object. (Inherited from Object.)|
|ToString||Returns a string that represents the current object. (Inherited from Object.)|
|_Attribute.GetIDsOfNames||Maps a set of names to a corresponding set of dispatch identifiers. (Inherited from Attribute.)|
|_Attribute.GetTypeInfo||Retrieves the type information for an object, which can be used to get the type information for an interface. (Inherited from Attribute.)|
|_Attribute.GetTypeInfoCount||Retrieves the number of type information interfaces that an object provides (either 0 or 1). (Inherited from Attribute.)|
|_Attribute.Invoke||Provides access to properties and methods exposed by an object. (Inherited from Attribute.)|
Use this attribute to represent an association in a database, such as the relationship between a foreign key and a primary key.
In the following example, the Order class includes an attribute to associate Orders with Customers.
Private _Customer As EntityRef(Of Customer) <Association(Name:="FK_Orders_Customers", Storage:="_Customer", ThisKey:="CustomerID", IsForeignKey:=True)> _ Public Property Customer() As Customer Get Return Me._Customer.Entity End Get Set(ByVal value As Customer) Dim previousValue As Customer = Me._Customer.Entity If (((previousValue Is value) _ = False) _ OrElse (Me._Customer.HasLoadedOrAssignedValue = False)) Then Me.SendPropertyChanging() If ((previousValue Is Nothing) _ = False) Then Me._Customer.Entity = Nothing previousValue.Orders.Remove(Me) End If Me._Customer.Entity = value If ((value Is Nothing) _ = False) Then value.Orders.Add(Me) Me._CustomerID = value.CustomerID Else Me._CustomerID = CType(Nothing, String) End If Me.SendPropertyChanged("Customer") End If End Set End Property
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.