Work with Parallel Activity in Workflow

Parallel activity define a number of activity sequences that run in Parallel.

Introduction : The Parallel activity allows multiple activities to execute at the same time. This does not mean the Parallel activity permits parallel processing across multiple threads - only a single thread will execute inside of a workflow. Instead, the Parallel activity allows separate branches inside the activity to execute independently.

Let see how to create Parallel activity :

Step : 1 Create an Workflow Console Application.

• Open Visual Studio.
• Select File->New->Project.
• Select Workflow Console Application.

Step : 2  Drag Flowchart activity to the designer to place the different activities anywhere on the palette.

Step : 3  Drag a FlowSwitch activity to the bottom of the Workflow.

Step : 4  Drag a WriteLine activity to display a standard greeting message and set the Display Name Winter, Spring, Summer , Autumn and Default.

Step : 5  Drag a Parallel activity to the bottom of Workflow. Draw a connection from each of the WriteLine activities to the Parallel activity.

Adding the Branches :

Step : 6  Double click in Parallel activity and drag three WriteLine activities. One of these activities will display the

• Date.
• Time.
• Day of  the week.

Enter one of these expression for the Text property on each of the WriteLine activities.

Expression :

"Time: " + DateTime.Now.TimeOfDay.ToString()
"Date: " + DateTime.Now.Date.ToShortDateString()
"Today is: " + DateTime.Now.ToString("dddd")

Step : 7 Open program.cs file and write a code.

Code :

using System;
using System.Linq;
using System.Activities;
using System.Activities.Statements;
namespace WorkflowConsoleApplication11
{
 class Program
    {
        static void Main(string[] args)
        {
            WorkflowInvoker.Invoke(new Workflow1());
            Console.WriteLine("Hello");
            Console.WriteLine("Press Enter to exit");
            Console.ReadLine();
        }
    }
}
Step : 8 PressF5 and run application.