ReplicatorActivity in Workflow

Introduction : The Replicator Activity enables you to create an arbitrary number of instances of a single activity during run time. Each ReplicatorActivity can contain only one child activity, but the child can be a composite activity. The Replicator Activity finishes when all child activities have finished. The Replicator Activity can be use in two way.

Sequence Type.
Parallel Type.

When we use the Unit Condition property to stop execution of the Replicator Activity before the completion of the child activity instance. The Replicator Activity is similar to a ForEach statement in code.

Step 1 : Open Visual Studio 2010.

Go to File-> New-> Project.
Select Sequential Workflow Console Application.

Step 2 : Drag activity form Toolbox.

Drag Replicator, Sequence, Delay, Code activity.

Step 3 : Now we select Replicator Activity and right -click.

Go to the properties option and define InitialChildData, Execution Type.

Step 4 : Again select the Delay activity and right-click.

Define TimeOutDuration.

Step 5 : Go to the Solution Explorer and select program.cs.

Write the below code.

Code :

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading;
using System.Workflow.Runtime;
using System.Workflow.Runtime.Hosting;
namespace WorkflowConsoleApplication17
{
class Program
{
static void Main(string[] args)
{
using (WorkflowRuntime workflowRuntime = new WorkflowRuntime())
{
AutoResetEvent waitHandle = new AutoResetEvent(false);
workflowRuntime.WorkflowCompleted += delegate(object sender, WorkflowCompletedEventArgs e) { waitHandle.Set(); };
workflowRuntime.WorkflowTerminated += delegate(object sender, WorkflowTerminatedEventArgs e)
{
Console.WriteLine(e.Exception.Message);
Console.ReadLine();
waitHandle.Set();
};
WorkflowInstance instance = workflowRuntime.CreateWorkflow(typeof(WorkflowConsoleApplication17.Workflow1));
instance.Start();
waitHandle.WaitOne();
}
}
}
}

Step 6 : Go to Workflow1.Designer.cs option and right a code for the DependencyProperty that is created using the DependencyProperty.RegisterAttached() function.

Code :

public static DependencyProperty LoopValueProperty = DependencyProperty.RegisterAttached("LoopValue", typeof(int), typeof(Workflow1));

Step 7 : Go to Workflow1.cs[Design] and select code activity.

Double-click in code activity define the ReplicatorActivity works in sequential mode.

Code :

private void codeActivity1_ExecuteCode(object sender, EventArgs e)
{
int value = (int)replicatorActivity1.CurrentChildData[replicatorActivity1.CurrentIndex];
Console.WriteLine("Loop value = {1}", value);
}
private void codeActivity1_ExecuteCode_1(object sender, EventArgs e)
{
Activity activity = (Activity)sender;
int value = (int)activity.Parent.GetValue(LoopValueProperty);
Console.WriteLine("The current value = {0}", value);
}

Step 8 : GO to Workflow1.Designer.cs option and define the complete code for the Parallel and Sequence mode.

Code :

using System;
using System.ComponentModel;
using System.ComponentModel.Design;
using System.Collections.Generic;
using System.Collections;
using System.Linq;
using System.Workflow.ComponentModel.Compiler;
using System.Workflow.ComponentModel.Serialization;
using System.Workflow.ComponentModel;
using System.Workflow.ComponentModel.Design;
using System.Workflow.Runtime;
using System.Workflow.Activities;
using System.Workflow.Activities.Rules;
using System.Data;
using System.Diagnostics;
namespace WorkflowConsoleApplication17
{
public sealed partial class Workflow1 : SequentialWorkflowActivity
{
public Workflow1()
{
InitializeComponent();
}
public static DependencyProperty LoopValueProperty = DependencyProperty.RegisterAttached("LoopValue", typeof(int), typeof(Workflow1));
private void replicatorActivity1_Initialized_1(object sender, EventArgs e)
{
ReplicatorActivity replicator = (ReplicatorActivity)sender;
replicator.InitialChildData = new List<int>(Enumerable.Range(1, 5));
}
private void delayActivity1_InitializeTimeoutDuration(object sender, EventArgs e)
{
DelayActivity delay = (DelayActivity)sender;
Random random = new Random();
delay.TimeoutDuration = TimeSpan.FromSeconds(random.Next(5));
}
private void replicatorActivity1_ChildInitialized(object sender, ReplicatorChildEventArgs e)
{
e.Activity.SetValue(LoopValueProperty, e.InstanceData);
}
private void codeActivity1_ExecuteCode(object sender, EventArgs e)
{
int value = (int)replicatorActivity1.CurrentChildData[replicatorActivity1.CurrentIndex];
Console.WriteLine("Loop value = {1}", value);
}
private void codeActivity1_ExecuteCode_1(object sender, EventArgs e)
{
Activity activity = (Activity)sender;
int value = (int)activity.Parent.GetValue(LoopValueProperty);
Console.WriteLine("The current value = {0}", value);
}
public IList replicatorActivity1_InitialChildData1 = default(System.Collections.IList);
}
}

Step 9 : Press F5 and run the application.