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NativeActivity<TResult> Class

  • Reference

Definition

Namespace:
System.Activities
Assembly:
System.Activities.dll

Abstract base class for custom activities that implement execution logic using the Execute(NativeActivityContext) method, that has full access to the runtime's features.

generic <typename TResult>
public ref class NativeActivity abstract : System::Activities::Activity<TResult>
public abstract class NativeActivity<TResult> : System.Activities.Activity<TResult>
type NativeActivity<'Result> = class
    inherit Activity<'Result>
Public MustInherit Class NativeActivity(Of TResult)
Inherits Activity(Of TResult)

Type Parameters

TResult

The result returned by the activity.

Inheritance
Object
Activity
ActivityWithResult
Activity<TResult>
NativeActivity<TResult>
Derived

Examples

The following code sample demonstrates creating a class that inherits from NativeActivity<TResult>. This example is from the How to: Create an Activity step of the Getting Started Tutorial [.NET Framework 4.5].

public sealed class ReadInt : NativeActivity<int>
{
    [RequiredArgument]
    public InArgument<string> BookmarkName { get; set; }

    protected override void Execute(NativeActivityContext context)
    {
        string name = BookmarkName.Get(context);

        if (string.IsNullOrEmpty(name))
        {
            throw new ArgumentException("BookmarkName cannot be an Empty string.",
                "BookmarkName");
        }

        context.CreateBookmark(name, new BookmarkCallback(OnReadComplete));
    }

    // NativeActivity derived activities that do asynchronous operations by calling
    // one of the CreateBookmark overloads defined on System.Activities.NativeActivityContext
    // must override the CanInduceIdle property and return true.
    protected override bool CanInduceIdle
    {
        get { return true; }
    }

    void OnReadComplete(NativeActivityContext context, Bookmark bookmark, object state)
    {
        this.Result.Set(context, Convert.ToInt32(state));
    }
}

Public NotInheritable Class ReadInt
    Inherits NativeActivity(Of Integer)
    
    <RequiredArgument()>
    Property BookmarkName() As InArgument(Of String)

    Protected Overrides Sub Execute(ByVal context As NativeActivityContext)
        Dim name As String
        name = BookmarkName.Get(context)

        If name = String.Empty Then
            Throw New ArgumentException("BookmarkName cannot be an Empty string.",
                "BookmarkName")
        End If

        context.CreateBookmark(name, New BookmarkCallback(AddressOf OnReadComplete))
    End Sub

    ' NativeActivity derived activities that do asynchronous operations by calling 
    ' one of the CreateBookmark overloads defined on System.Activities.NativeActivityContext 
    ' must override the CanInduceIdle property and return True.
    Protected Overrides ReadOnly Property CanInduceIdle As Boolean
        Get
            Return True
        End Get
    End Property

    Sub OnReadComplete(ByVal context As NativeActivityContext, ByVal bookmark As Bookmark, ByVal state As Object)
        Result.Set(context, Convert.ToInt32(state))
    End Sub

End Class

Constructors

NativeActivity<TResult>()

When implemented in a derived class, creates a new instance of the derived class.

Properties

CacheId

Gets the identifier of the cache that is unique within the scope of the workflow definition.

(Inherited from Activity)
CanInduceIdle

Gets or sets a value that indicates whether the activity can cause the workflow to become idle.
Constraints

Gets a collection of Constraint activities that can be configured to provide validation for the Activity.

(Inherited from Activity)
DisplayName

Gets or sets an optional friendly name that is used for debugging, validation, exception handling, and tracking.

(Inherited from Activity)
Id

Gets an identifier that is unique in the scope of the workflow definition.

(Inherited from Activity)
Implementation

The execution logic of the activity.
ImplementationVersion

Gets or sets the implementation version of the activity.
ImplementationVersion

Gets or sets the version of the implementation used.

(Inherited from Activity)
Result

Gets or sets the result argument for the Activity<TResult>.

(Inherited from Activity<TResult>)
ResultType

When implemented in a derived class, gets the type of an activity OutArgument.

(Inherited from ActivityWithResult)

Methods

Abort(NativeActivityAbortContext)

When implemented in a derived class, takes actions in response to the activity being aborted.
CacheMetadata(ActivityMetadata)

Not implemented. Use CacheMetadata(NativeActivityMetadata) instead.
CacheMetadata(NativeActivityMetadata)

Creates and validates a description of the activity's arguments, variables, child activities, and activity delegates.
Cancel(NativeActivityContext)

When implemented in a derived class, runs logic to cause graceful early completion of the activity.
Equals(Object)

Determines whether the specified object is equal to the current object.

(Inherited from Object)
Execute(NativeActivityContext)

When implemented in a derived class, runs the activity's execution logic.
GetHashCode()

Serves as the default hash function.

(Inherited from Object)
GetType()

Gets the Type of the current instance.

(Inherited from Object)
MemberwiseClone()

Creates a shallow copy of the current Object.

(Inherited from Object)
OnCreateDynamicUpdateMap(NativeActivityUpdateMapMetadata, Activity)

Raises an event when creating a map for the dynamic update.
OnCreateDynamicUpdateMap(UpdateMapMetadata, Activity)

Raises an event when creating a map for the dynamic update.
OnCreateDynamicUpdateMap(UpdateMapMetadata, Activity)

Raises an event when creating dynamic update map.

(Inherited from Activity)
ShouldSerializeDisplayName()

Indicates whether the DisplayName property should be serialized.

(Inherited from Activity)
ToString()

Returns a String that contains the Id and DisplayName of the Activity.

(Inherited from Activity)
UpdateInstance(NativeActivityUpdateContext)

Updates the instance of NativeActivity<TResult>.

Applies to