CorrelationAliasAttribute Class (System.Workflow.Activities)

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.NET Framework Class Library
CorrelationAliasAttribute Class

Overrides the correlation parameter value when the correlation value must be obtained from a parameter other than that indicated by the CorrelationParameterAttribute. This class cannot be inherited.

Inheritance Hierarchy
System.Object
  System.Attribute
    System.Workflow.Activities.CorrelationAliasAttribute

Namespace:  System.Workflow.Activities
Assembly:  System.Workflow.Activities (in System.Workflow.Activities.dll)
Syntax
Visual Basic
<AttributeUsageAttribute(AttributeTargets.Method Or AttributeTargets.Event Or AttributeTargets.Delegate, AllowMultiple := True)> _
Public NotInheritable Class CorrelationAliasAttribute _
	Inherits Attribute
C#
[AttributeUsageAttribute(AttributeTargets.Method|AttributeTargets.Event|AttributeTargets.Delegate, AllowMultiple = true)]
public sealed class CorrelationAliasAttribute : Attribute
Visual C++
[AttributeUsageAttribute(AttributeTargets::Method|AttributeTargets::Event|AttributeTargets::Delegate, AllowMultiple = true)]
public ref class CorrelationAliasAttribute sealed : public Attribute
F#
[<Sealed>]
[<AttributeUsageAttribute(AttributeTargets.Method|AttributeTargets.Event|AttributeTargets.Delegate, AllowMultiple = true)>]
type CorrelationAliasAttribute =  
    class
        inherit Attribute
    end

The CorrelationAliasAttribute type exposes the following members.

Constructors
  Name Description
Public method CorrelationAliasAttribute Initializes a new instance of the CorrelationAliasAttribute with the name of the correlation that is being aliased and the path to where the value can be found.
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Properties
  Name Description
Public property Name Gets the name of the correlation parameter that is being aliased.
Public property Path Gets the path within the parameter that specifies the location of the correlation value.
Public property TypeId When implemented in a derived class, gets a unique identifier for this Attribute. (Inherited from Attribute.)
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Methods
  Name Description
Public method Equals Infrastructure. Returns a value that indicates whether this instance is equal to a specified object. (Inherited from Attribute.)
Protected method Finalize Allows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection. (Inherited from Object.)
Public method GetHashCode Returns the hash code for this instance. (Inherited from Attribute.)
Public method GetType Gets the Type of the current instance. (Inherited from Object.)
Public method 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.)
Public method Match When overridden in a derived class, returns a value that indicates whether this instance equals a specified object. (Inherited from Attribute.)
Protected method MemberwiseClone Creates a shallow copy of the current Object. (Inherited from Object.)
Public method ToString Returns a string that represents the current object. (Inherited from Object.)
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Explicit Interface Implementations
  Name Description
Explicit interface implemetation Private method _Attribute.GetIDsOfNames Maps a set of names to a corresponding set of dispatch identifiers. (Inherited from Attribute.)
Explicit interface implemetation Private method _Attribute.GetTypeInfo Retrieves the type information for an object, which can be used to get the type information for an interface. (Inherited from Attribute.)
Explicit interface implemetation Private method _Attribute.GetTypeInfoCount Retrieves the number of type information interfaces that an object provides (either 0 or 1). (Inherited from Attribute.)
Explicit interface implemetation Private method _Attribute.Invoke Provides access to properties and methods exposed by an object. (Inherited from Attribute.)
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Remarks

To match an incoming message with the appropriate workflow instance, the message and the workflow instance must share a key. This key is called a correlation set. Typically, the key can be a single-valued correlation set. This means that an ID field in the message can be matched against an ID of the same type that is held by schedule instances.

The CorrelationAliasAttribute is applied to a method or an event on an interface on a data exchange interface.

Examples

The following code example shows how to use a CorrelationAliasAttribute to override a CorrelationParameterAttribute. This code example is from the CorrelatedLocalService SDK sample. For more information, seeCorrelated Local Service Sample.

C#

[ExternalDataExchange]
[CorrelationParameter("taskId")]
public interface ITaskService2
{
    [CorrelationInitializer]
    void CreateTask(string taskId, string assignee, string text);

    [CorrelationAlias("taskId", "e.Id")]
    event EventHandler<TaskEventArgs> TaskCompleted;
}
Version Information

.NET Framework

Supported in: 4, 3.5, 3.0
Platforms

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

Reference

System.Workflow.Activities Namespace