# .NET and More > Silverlight >  Error while adding service in silverlight application

## ERUM

```
using System.Data;
using System.Data.SqlClient;
 
using System;
using System.Linq;
using System.Runtime.Serialization;
using System.ServiceModel;
using System.ServiceModel.Activation;
using System.Collections.Generic;
using System.Text;

namespace SilverlightWithWCFService.Web
{
    [ServiceContract(Namespace = "")]
    [AspNetCompatibilityRequirements(RequirementsMode = AspNetCompatibilityRequirementsMode.Allowed)]
    public class SampleService
    {
    
          [OperationContract]
        public string GetName() 
        {
            return "John";
        }
    }
}
```



```
using System;

using System.Collections.Generic;
using System.Linq;
using System.Net;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Animation;
using System.Windows.Shapes;
using System.ServiceModel;
using SilverlightWithWCFService.CustomerService;

namespace SilverlightWithWCFService
{
    public partial class MainPage : UserControl
    {
        public MainPage()
        {
            InitializeComponent();
            SampleServiceClient client = new SampleServiceClient();
            client.CustomerListCompleted += new EventHandler<CustomerListCompletedEventArgs>(client_CustomerListCompleted);
            client.CustomerListAsync();

            client.GetNameCompleted += new EventHandler(client_GetNameCompleted);
            client.GetNameAsync();

        
        }
        void client_CustomerListCompleted(object sender, CustomerListCompletedEventArgs e)
        {
            CustomerGrid.ItemsSource = e.Result;
        }

        void client_GetNameCompleted(object sender, SampleService.GetNameCompletedEventArgs e)
        {
            textblock1.Text = (string)e.Result;
        }
        void Func(string s)
        {

            
        }

    }
}
```

but it gives error as "Error 1 The type name 'GetNameCompletedEventArgs' does not exist in the type 'SilverlightWithWCFService.CustomerService.SampleService' C:\Users\.................e\MainPage.xaml.cs 38 67 SilverlightWithWCFService
"

Also let me add few more thing 

 i added this method after customerlist ,also its hsowingh me that method when i click on discover or go button in window,Rebuilt the solution too 

any idea

----------

