WCF Service in Workflow

Introduction : The Window Communication Foundation (WCF) is service-oriented application. With the help of WCF we can send a data from one service to another. The Workflow is simply encapsulate activities for Window Communication Foundation. WCF is designed to offer a manageable approach to creating Web services and Web service clients.

Step 1 : Open Visual Studio.

Select File->New->Project.
Select WCF Workflow Service Application.
Click OK.

After OK the following activity show.

Step 2 : Drag activity from Toolbox.

Drag Flowchart activity.

Step 3 : Define Variables for application.

Select Sequence Activity.
Click in Variables option.
Define Name, Variables Type.

Step 4 : Go to Solution Explorer and right-click in project option.

Select Add->New Item.
Select Code Activity.

Write down the following code:

Code :

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Activities;
using System.IO;
namespace DeclarativeServiceLibrary1
{
public sealed class CodeActivity1 : CodeActivity
{
// Define an activity input argument of type string
public InArgument<string> Text { get; set; }
// If your activity returns a value, derive from CodeActivity<TResult>
// and return the value from the Execute method.
public OutArgument<string> result { get; set; }
protected override void Execute(CodeActivityContext context)
{
// Obtain the runtime value of the Text input argument
string text = context.GetValue(this.Text);
File.AppendAllText(@"C:\WorkflowLog.txt", "Result is:" + text);
context.SetValue(result, "Result is:" + text);
}
}
}

Step 5 : Go to the Design option.