AssociationAttribute Class

AssociationAttribute Class

 

Designates a property to represent a database association, such as a foreign key relationship.

Namespace:   System.Data.Linq.Mapping
Assembly:  System.Data.Linq (in System.Data.Linq.dll)

System.Object
  System.Attribute
    System.Data.Linq.Mapping.DataAttribute
      System.Data.Linq.Mapping.AssociationAttribute

[AttributeUsageAttribute(AttributeTargets.Property | AttributeTargets.Field, 
	AllowMultiple = false)]
public sealed class AssociationAttribute : DataAttribute

NameDescription
System_CAPS_pubmethodAssociationAttribute()

Initializes a new instance of the AssociationAttribute class.

NameDescription
System_CAPS_pubpropertyDeleteOnNull

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.

System_CAPS_pubpropertyDeleteRule

Gets or sets delete behavior for an association.

System_CAPS_pubpropertyIsForeignKey

Gets or sets the member as the foreign key in an association representing a database relationship.

System_CAPS_pubpropertyIsUnique

Gets or sets the indication of a uniqueness constraint on the foreign key.

System_CAPS_pubpropertyName

Gets or sets the name of a column.(Inherited from DataAttribute.)

System_CAPS_pubpropertyOtherKey

Gets or sets one or more members of the target entity class as key values on the other side of the association.

System_CAPS_pubpropertyStorage

Gets or sets a private storage field to hold the value from a column.(Inherited from DataAttribute.)

System_CAPS_pubpropertyThisKey

Gets or sets members of this entity class to represent the key values on this side of the association.

System_CAPS_pubpropertyTypeId

When implemented in a derived class, gets a unique identifier for this Attribute.(Inherited from Attribute.)

NameDescription
System_CAPS_pubmethodEquals(Object)

This API supports the product infrastructure and is not intended to be used directly from your code. Returns a value that indicates whether this instance is equal to a specified object.(Inherited from Attribute.)

System_CAPS_pubmethodGetHashCode()

Returns the hash code for this instance.(Inherited from Attribute.)

System_CAPS_pubmethodGetType()

Gets the Type of the current instance.(Inherited from Object.)

System_CAPS_pubmethodIsDefaultAttribute()

When overridden in a derived class, indicates whether the value of this instance is the default value for the derived class.(Inherited from Attribute.)

System_CAPS_pubmethodMatch(Object)

When overridden in a derived class, returns a value that indicates whether this instance equals a specified object.(Inherited from Attribute.)

System_CAPS_pubmethodToString()

Returns a string that represents the current object.(Inherited from Object.)

NameDescription
System_CAPS_pubinterfaceSystem_CAPS_privmethod_Attribute.GetIDsOfNames(Guid, IntPtr, UInt32, UInt32, IntPtr)

Maps a set of names to a corresponding set of dispatch identifiers.(Inherited from Attribute.)

System_CAPS_pubinterfaceSystem_CAPS_privmethod_Attribute.GetTypeInfo(UInt32, UInt32, IntPtr)

Retrieves the type information for an object, which can be used to get the type information for an interface.(Inherited from Attribute.)

System_CAPS_pubinterfaceSystem_CAPS_privmethod_Attribute.GetTypeInfoCount(UInt32)

Retrieves the number of type information interfaces that an object provides (either 0 or 1).(Inherited from Attribute.)

System_CAPS_pubinterfaceSystem_CAPS_privmethod_Attribute.Invoke(UInt32, Guid, UInt32, Int16, IntPtr, IntPtr, IntPtr, IntPtr)

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 AssociationAttribute attribute to associate Orders with Customers.

   private EntityRef<Customer> _Customer;
// ...
[Association(Name="FK_Orders_Customers", Storage="_Customer", ThisKey="CustomerID", IsForeignKey=true)]
public Customer Customer
{
	get
	{
		return this._Customer.Entity;
	}
	set
	{
		Customer previousValue = this._Customer.Entity;
		if (((previousValue != value) 
					|| (this._Customer.HasLoadedOrAssignedValue == false)))
		{
			this.SendPropertyChanging();
			if ((previousValue != null))
			{
				this._Customer.Entity = null;
				previousValue.Orders.Remove(this);
			}
			this._Customer.Entity = value;
			if ((value != null))
			{
				value.Orders.Add(this);
				this._CustomerID = value.CustomerID;
			}
			else
			{
				this._CustomerID = default(string);
			}
			this.SendPropertyChanged("Customer");
		}
	}
}

.NET Framework
Available since 3.5
Windows Phone Silverlight
Available since 7.1

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

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