using System;

public class Program // Consider this your home form

{

    public void Main()

    {

        var serviceController = new ServiceController();

        serviceController.ServiceStateChange += ServiceController_ServiceStateChanged;

        serviceController.StartServices();

    }

    private void ServiceController_ServiceStateChanged(object sender, ServiceControllerEventArgs e)

    {

        // Add to listbox or do whatever you want. I am just printing.

        Console.WriteLine(e.Message);

    }

}

​

public class ServiceController

{

    public event EventHandler<ServiceControllerEventArgs> ServiceStateChange;

    public void StartServices()

    {

        Service[] services = new Service[] // Sample services data

        { 

            new Service { Name = "MSMQ", Status = "Stopped" },

            new Service { Name = "W3SVC", Status = "Running" }

        };

        string message = null;

        foreach(Service s in services) 

        {

            if(s.Status == "Stopped") 

            {

                s.Start();

                // Assuming it starts almost immediately. If not, you could follow same pattern for 

                // Service class where an event will be raised once service is "actually" started.

                if(s.Status == "Running") {

                    message = string.Format("Service {0} is {1}", s.Name, s.Status);

                }

            }

            else if(s.Status == "Running") {

                message = string.Format("Service {0} is already {1}", s.Name, s.Status);

            }

            // Now tell subscriber (home form) about this.

            OnServiceStateChange(message);

        }

    }

    private void OnServiceStateChange(string message)

    {

        var serviceStateChangeHandler = ServiceStateChange;

        if(serviceStateChangeHandler != null)

        {

            serviceStateChangeHandler(this, new ServiceControllerEventArgs { Message = message });

        }

    }

}

​

// You could have custome delegate type for event to return string message.

// But IMO this is much cleaner, and as per MSFT guidelines.

public class ServiceControllerEventArgs : EventArgs

{

    // You can also return Service instance

    // Just including Message for now 

    public string Message { get; set; }

}

​

// for demo purpose, represents individual service.

public class Service

{

    public string Name { get; set; }

    public string Status { get; set; }

    public void Start() {

        Status = "Running";

    }

}