Open Ria Services

https://openriaservices.gitbook.io/openriaservices/
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Open Ria Services simplifies the development of n-tier solutions for Rich Internet Applications...
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### Query documentation via HTTP GET

Source: https://openriaservices.gitbook.io/openriaservices/llms.txt

Perform a GET request to the documentation index with 'ask' and 'goal' parameters to receive a tailored answer.

```http
GET https://openriaservices.gitbook.io/openriaservices/readme.md?ask=<question>&goal=<end_goal>
```

--------------------------------

### Get Products Method with Ordering

Source: https://openriaservices.gitbook.io/openriaservices/gg602749/ee807305.md

Configures the query to return products ordered by ProductID for Entity Framework compatibility.

```csharp
public IQueryable<Product> GetProducts()
{
  return this.ObjectContext.Products.OrderBy(p => p.ProductID);
}
```

```vb
Public Function GetProducts() As IQueryable(Of Product)
  Return Me.ObjectContext.Products.OrderBy(Function(p) p.ProductID)
End Function
```

--------------------------------

### Implement Custom Authorization Attribute

Source: https://openriaservices.gitbook.io/openriaservices/ee707361/ee707357.md

Examples of creating custom authorization attributes by overriding the Authorize or IsAuthorized methods.

```vb
Public Class CheckAttendeeNameAttribute Inherits System.Web.DomainServices.AuthorizationAttribute

    Public Overrides Function Authorize(ByVal principal As System.Security.Principal.IPrincipal) As Boolean
        If (principal.IsInRole("Attendee") And principal.Identity.Name.StartsWith("A")) Then
            Return True
        Else
            Return False
        End If
    End Function
End Class
```

```vb
Public Class RestrictAccessToAssignedManagers
    Inherits AuthorizationAttribute

    Protected Overrides Function IsAuthorized(ByVal principal As System.Security.Principal.IPrincipal, ByVal authorizationContext As System.ComponentModel.DataAnnotations.AuthorizationContext) As System.ComponentModel.DataAnnotations.AuthorizationResult
        Dim eph As EmployeePayHistory
        Dim selectedEmployee As Employee
        Dim authenticatedUser As Employee

        eph = CType(authorizationContext.Instance, EmployeePayHistory)

        Using context As New AdventureWorksEntities()
            selectedEmployee = context.Employees.SingleOrDefault(Function(e) e.EmployeeID = eph.EmployeeID)
            authenticatedUser = context.Employees.SingleOrDefault(Function(e) e.LoginID = principal.Identity.Name)
        End Using

        If (selectedEmployee.ManagerID = authenticatedUser.EmployeeID) Then
            Return AuthorizationResult.Allowed
        Else
            Return New AuthorizationResult("Only the authenticated manager for the employee can add a new record.")
        End If
    End Function
End Class
```

```csharp
public class CheckAttendeeNameAttribute : System.Web.DomainServices.AuthorizationAttribute
{

    public override bool Authorize(System.Security.Principal.IPrincipal principal)
    {
        if (principal.IsInRole("Attendee") && principal.Identity.Name.StartsWith("A"))
        {
            return true;
        }
        else
        {
            return false;
        }
    }
}
```

```csharp
public class RestrictAccessToAssignedManagers : AuthorizationAttribute
{
    protected override AuthorizationResult IsAuthorized(System.Security.Principal.IPrincipal principal, AuthorizationContext authorizationContext)
    {
        EmployeePayHistory eph = (EmployeePayHistory)authorizationContext.Instance;
        Employee selectedEmployee;
        Employee authenticatedUser;

        using (AdventureWorksEntities context = new AdventureWorksEntities())
        {
            selectedEmployee = context.Employees.SingleOrDefault(e => e.EmployeeID == eph.EmployeeID);
            authenticatedUser = context.Employees.SingleOrDefault(e => e.LoginID == principal.Identity.Name);
        }

        if (selectedEmployee.ManagerID == authenticatedUser.EmployeeID)
        {
            return AuthorizationResult.Allowed;
        }
        else
        {
            return new AuthorizationResult("Only the authenticated manager for the employee can add a new record.");
        }
    }
}
```

--------------------------------

### Configure Authentication Service on Startup

Source: https://openriaservices.gitbook.io/openriaservices/ee707361/ee707353.md

Load the user state during application startup to initialize the authentication context.

```vbnet
Private Sub Application_Startup(ByVal o As Object, ByVal e As StartupEventArgs) Handles Me.Startup
    WebContext.Current.Authentication.LoadUser(AddressOf OnLoadUser_Completed, Nothing)
    Me.RootVisual = New MainPage()
End Sub

Private Sub OnLoadUser_Completed(ByVal operation As LoadUserOperation)
    ' Update UI, if necessary
End Sub
```

```csharp
private void Application_Startup(object sender, StartupEventArgs e)
{
    WebContext.Current.Authentication.LoadUser(OnLoadUser_Completed, null);
    this.RootVisual = new MainPage();
}

private void OnLoadUser_Completed(LoadUserOperation operation)
{
    // update UI, if necessary
}
```

--------------------------------

### Data Bind to Computed Property

Source: https://openriaservices.gitbook.io/openriaservices/ee707349/ee707345/ee707331.md

Example of binding a UI element to the newly created computed property.

```xml
<dataForm:DataField Label="Total Off Hours"> 
  <TextBox Text="{Binding TotalOffHours, Mode=OneWay}" />
</dataForm:DataField>
```

--------------------------------

### Initialize Page Constructor

Source: https://openriaservices.gitbook.io/openriaservices/ee707361/ee942451.md

Load reports and configure UI visibility for authenticated users upon page initialization.

```vbnet
Public Sub New()
    InitializeComponent()
    LoadReports()
    If (WebContext.Current.User.IsAuthenticated) Then
        SettingsButton.Visibility = System.Windows.Visibility.Visible
    End If
End Sub
```

--------------------------------

### Implement Database Initializer

Source: https://openriaservices.gitbook.io/openriaservices/ee707336/hh556025.md

Implements a custom initializer that seeds the database with initial Product and Category data.

```csharp
    public class ProductDbContextInitializer : DropCreateDatabaseAlways<ProductDbContext>
    {
        protected override void Seed(ProductDbContext context)
        {
            Category[] categories = new Category[]
            {
                new Category { CategoryID = 1, CategoryName = "Food", Description = "Edible stuff",
                    Products = new Product[] { 
                        new Product { ProductID = 1, ProductName = "Candy", UnitPrice = 10},
                        new Product { ProductID = 2, ProductName = "Fruits", UnitPrice = 20, Discontinued = true },
                        new Product { ProductID = 5, ProductName = "Cereal", UnitPrice = 10},
                    }.ToList()},
                new Category { CategoryID = 2, CategoryName = "Clothes", Description = "Personal stuff",
                    Products = new Product[] { 
                        new Product { ProductID = 3, ProductName = "Shirt", UnitPrice = 50},
                        new Product { ProductID = 4, ProductName = "Cap", UnitPrice = 15},
                    }.ToList()},
                new Category { CategoryID = 3, CategoryName = "Furniture", Description = "Household stuff",
                    Products = new Product[] { 
                        new Product { ProductID = 6, ProductName = "Table", UnitPrice = 100},
                        new Product { ProductID = 7, ProductName = "Chair", UnitPrice = 60},
                        new Product { ProductID = 8, ProductName = "Lamp", UnitPrice = 20, Discontinued = true },
                    }.ToList()},
            };
            foreach (var category in categories)
            {
                context.Categories.Add(category);
            }
        }
```

--------------------------------

### Initialize Page Constructor

Source: https://openriaservices.gitbook.io/openriaservices/ee707361/ee942449.md

Sets up event handlers and initial data loading within the page constructor.

```vbnet
Public Sub New()
    InitializeComponent()

    Me.Title = ApplicationStrings.ReportsPageTitle

    AddHandler WebContext.Current.Authentication.LoggedIn, AddressOf Authentication_LoggedIn
    AddHandler WebContext.Current.Authentication.LoggedOut, AddressOf Authentication_LoggedOut

    LoadReports()
End Sub
```

```csharp
public Reports()
{
    InitializeComponent();

    this.Title = ApplicationStrings.ReportsPageTitle;

    WebContext.Current.Authentication.LoggedIn += new System.EventHandler<AuthenticationEventArgs>(Authentication_LoggedIn);
    WebContext.Current.Authentication.LoggedOut += new System.EventHandler<AuthenticationEventArgs>(Authentication_LoggedOut);

    LoadReports();
}
```

--------------------------------

### Initialize WebContext in Client Application

Source: https://openriaservices.gitbook.io/openriaservices/ee707361/ee707353.md

Configure the WebContext with an authentication provider and add it to the application lifetime objects during startup.

```vbnet
Public Sub New()
    InitializeComponent()

    Dim webcontext As New WebContext
    webcontext.Authentication = New OpenRiaServices.Client.Authentication.FormsAuthentication
    Me.ApplicationLifetimeObjects.Add(webcontext)
End Sub
```

```csharp
public App()
{
    this.Startup += this.Application_Startup;
    this.UnhandledException += this.Application_UnhandledException;

    InitializeComponent();

    WebContext webcontext = new WebContext();
    webcontext.Authentication = new OpenRiaServices.Client.Authentication.FormsAuthentication();
    this.ApplicationLifetimeObjects.Add(webcontext);
}
```

--------------------------------

### Configure Windows Authentication in App Startup

Source: https://openriaservices.gitbook.io/openriaservices/ee707336/ee707360.md

Update the application constructor to use WindowsAuthentication instead of FormsAuthentication.

```vb
Public Sub New()
    InitializeComponent()

    Dim webContext As New WebContext()
    'webContext.Authentication = New FormsAuthentication()
    webContext.Authentication = New WindowsAuthentication()
    Me.ApplicationLifetimeObjects.Add(webContext)
End Sub
```

```csharp
public App()
{
    InitializeComponent();

    WebContext webContext = new WebContext();
    //webContext.Authentication = new FormsAuthentication();
    webContext.Authentication = new WindowsAuthentication();
    this.ApplicationLifetimeObjects.Add(webContext);
}
```

--------------------------------

### Implement Child Window Logic

Source: https://openriaservices.gitbook.io/openriaservices/ee707336/ff713719.md

Code-behind to initialize the new entity and handle commit or cancel actions.

```vbnet
Partial Public Class EmployeeRegistrationWindow
    Inherits ChildWindow

    Public Sub New()
        InitializeComponent()
        NewEmployee = New Employee
        addEmployeeDataForm.CurrentItem = NewEmployee
        addEmployeeDataForm.BeginEdit()
    End Sub

    Public Property NewEmployee As Employee

    Private Sub OKButton_Click(ByVal sender As Object, ByVal e As RoutedEventArgs) Handles OKButton.Click
        Me.addEmployeeDataForm.CommitEdit()
        Me.DialogResult = True
    End Sub

    Private Sub CancelButton_Click(ByVal sender As Object, ByVal e As RoutedEventArgs) Handles CancelButton.Click
        NewEmployee = Nothing
        addEmployeeDataForm.CancelEdit()
        Me.DialogResult = False
    End Sub

End Class
```

```csharp
public partial class EmployeeRegistrationWindow : ChildWindow
{
    public EmployeeRegistrationWindow()
    {
        InitializeComponent();
        NewEmployee = new Employee();
        addEmployeeDataForm.CurrentItem = NewEmployee;
        addEmployeeDataForm.BeginEdit();    
    }

    public Employee NewEmployee { get; set; }

    private void OKButton_Click(object sender, RoutedEventArgs e)
    {
        addEmployeeDataForm.CommitEdit();
        this.DialogResult = true;
    }

    private void CancelButton_Click(object sender, RoutedEventArgs e)
    {
        NewEmployee = null;
        addEmployeeDataForm.CancelEdit();
        this.DialogResult = false;
    }
}
```

--------------------------------

### Implement Login Operation

Source: https://openriaservices.gitbook.io/openriaservices/ee707361/ee707353.md

Handle user login by passing credentials to the authentication service and processing the operation result.

```vbnet
Private Sub LoginButton_Click(ByVal sender As Object, ByVal e As RoutedEventArgs)
    Dim lp As LoginParameters = New LoginParameters(UserName.Text, Password.Password)
    WebContext.Current.Authentication.Login(lp, AddressOf Me.LoginOperation_Completed, Nothing)
    LoginButton.IsEnabled = False
    LoginResult.Text = ""
End Sub

Private Sub LoginOperation_Completed(ByVal lo As LoginOperation)
    If (lo.HasError) Then
        LoginResult.Text = lo.Error.Message
        LoginResult.Visibility = System.Windows.Visibility.Visible
        lo.MarkErrorAsHandled()
    ElseIf (lo.LoginSuccess = False) Then
        LoginResult.Text = "Login failed. Please check user name and password."
        LoginResult.Visibility = System.Windows.Visibility.Visible
    ElseIf (lo.LoginSuccess = True) Then
        SetControlVisibility(True)
    End If
    LoginButton.IsEnabled = True
End Sub
```

```csharp
private void LoginButton_Click(object sender, RoutedEventArgs e)
{
    LoginParameters lp = new LoginParameters(UserName.Text, Password.Password);
    WebContext.Current.Authentication.Login(lp, this.LoginOperation_Completed, null);
    LoginButton.IsEnabled = false;
    LoginResult.Text = "";
}

private void LoginOperation_Completed(LoginOperation lo)
{
    if (lo.HasError)
    {
        LoginResult.Text = lo.Error.Message;
        LoginResult.Visibility = System.Windows.Visibility.Visible;
        lo.MarkErrorAsHandled();
    }
    else if (lo.LoginSuccess == false)
    {
        LoginResult.Text = "Login failed. Please check user name and password.";
        LoginResult.Visibility = System.Windows.Visibility.Visible;
    }
    else if (lo.LoginSuccess == true)
    {
        SetControlVisibility(true);
    }
    LoginButton.IsEnabled = true;
}
```

--------------------------------

### Implement User Authentication and Registration in C#

Source: https://openriaservices.gitbook.io/openriaservices/ee707361/ee942451.md

Handles login, logout, and registration logic within a Silverlight or WPF Page. Requires OpenRiaServices.Client.Authentication and a generated DomainContext.

```csharp
using System;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Navigation;
using OpenRiaServices.Client.Authentication;
using OpenRiaServices.Client;
using System.ComponentModel.DataAnnotations;
using ExampleNavigationApplication.Web;

namespace ExampleNavigationApplication
{
    public partial class Home : Page
    {
        public Home()
        {
            InitializeComponent();

        }

        // Executes when the user navigates to this page.
        protected override void OnNavigatedTo(NavigationEventArgs e)
        {
            SetControlVisibility(WebContext.Current.User.IsAuthenticated);
        }

        private void LoginButton_Click(object sender, RoutedEventArgs e)
        {
            LoginParameters lp = new LoginParameters(UserName.Text, Password.Password);
            WebContext.Current.Authentication.Login(lp, this.LoginOperation_Completed, null);
            LoginButton.IsEnabled = false;
            LoginResult.Text = "";
        }

        private void LoginOperation_Completed(LoginOperation lo)
        {
            if (lo.HasError)
            {
                LoginResult.Text = lo.Error.Message;
                LoginResult.Visibility = System.Windows.Visibility.Visible;
                lo.MarkErrorAsHandled();
            }
            else if (lo.LoginSuccess == false)
            {
                LoginResult.Text = "Login failed. Please check user name and password.";
                LoginResult.Visibility = System.Windows.Visibility.Visible;
            }
            else if (lo.LoginSuccess == true)
            {
                SetControlVisibility(true);
            }
            LoginButton.IsEnabled = true;
        }

        private void SetControlVisibility(bool isAuthenticated)
        {
            if (isAuthenticated)
            {
                LoginBorder.Visibility = System.Windows.Visibility.Collapsed;
                RegisterBorder.Visibility = System.Windows.Visibility.Collapsed;
                WelcomeText.Text = "Welcome " + WebContext.Current.User.Name;
                WelcomeText.Visibility = System.Windows.Visibility.Visible;
                LogoutButton.Visibility = System.Windows.Visibility.Visible;
            }
            else
            {
                LoginBorder.Visibility = System.Windows.Visibility.Visible;
                RegisterBorder.Visibility = System.Windows.Visibility.Visible;
                WelcomeText.Visibility = System.Windows.Visibility.Collapsed;
                LogoutButton.Visibility = System.Windows.Visibility.Collapsed;
            }
        }

        private void LogoutButton_Click(object sender, RoutedEventArgs e)
        {
            WebContext.Current.Authentication.Logout(this.LogoutOperation_Completed, null);
        }

        private void LogoutOperation_Completed(LogoutOperation lo)
        {

            if (!lo.HasError)
            {
                SetControlVisibility(false);
            }
            else
            {
                ErrorWindow ew = new ErrorWindow("Logout failed.", "Please try logging out again.");
                ew.Show();
                lo.MarkErrorAsHandled();
            }
        }

        private void RegisterButton_Click(object sender, RoutedEventArgs e)
        {
            RegisterButton.IsEnabled = false;
            RegistrationDomainContext context = new RegistrationDomainContext();
            NewUser nu = new NewUser();
            try
            {
                nu.UserName = NewUsername.Text;
                nu.Password = NewPassword.Password;
                nu.Email = NewEmail.Text;
                nu.ConfirmPassword = NewConfirmPassword.Password;
                nu.RecordsToShow = int.Parse(DefaultRows.SelectionBoxItem.ToString());
                nu.SecurityQuestion = SecurityQuestion.Text;
                nu.SecurityAnswer = SecurityAnswer.Text;
                context.NewUsers.Add(nu);

                context.SubmitChanges(RegisterUser_Completed, null);
            }
            catch (ValidationException ve)
            {
                registerResult.Visibility = System.Windows.Visibility.Visible;
                registerResult.Text = ve.Message;
                RegisterButton.IsEnabled = true;
            }
        }
```

--------------------------------

### Handle Settings Button Click Event

Source: https://openriaservices.gitbook.io/openriaservices/ee707361/ee942451.md

Opens the ProfileWindow when the settings button is clicked.

```vbnet
Private Sub SettingsButton_Click(ByVal sender As Object, ByVal e As RoutedEventArgs)
    Dim settingsWindow = New ProfileWindow()
    settingsWindow.Show()
End Sub
```

```csharp
private void SettingsButton_Click(object sender, RoutedEventArgs e)
{
    Views.ProfileWindow settingsWindow = new Views.ProfileWindow();
    settingsWindow.Show();
}
```

--------------------------------

### Configure Profile in Web.config

Source: https://openriaservices.gitbook.io/openriaservices/ee707361/ee707350.md

Enable the profile system and define properties within the system.web section of the server project's configuration file.

```xml
<system.web>
  <authentication mode="Forms"></authentication>
  <profile enabled="true">
    <properties>
      <add name="FriendlyName"/>
    </properties>
  </profile>
</system.web>
```

--------------------------------

### Implement SettingsButton click handler

Source: https://openriaservices.gitbook.io/openriaservices/ee707361/ee942449.md

Event handler logic to instantiate and display the ProfileWindow when the settings link is clicked.

```vb
Private Sub SettingsButton_Click(ByVal sender As Object, ByVal e As RoutedEventArgs)
    Dim settingsWindow As New ProfileWindow
    settingsWindow.Show()
End Sub
```

```csharp
private void SettingsButton_Click(object sender, RoutedEventArgs e)
{
    ExampleBusinessApplication.Views.ProfileWindow settingsWindow = new ExampleBusinessApplication.Views.ProfileWindow();
    settingsWindow.Show();
}
```

--------------------------------

### Define a CustomerPresentationModel class

Source: https://openriaservices.gitbook.io/openriaservices/ee707348/ee707356/ee707347.md

Create a class in the server project with properties representing the desired fields from multiple entities. Ensure the class includes a property marked with the [Key] attribute.

```vbnet
Public Class CustomerPresentationModel
    <Key()> _
    Public Property CustomerID As Integer
    Public Property FirstName As String
    Public Property LastName As String
    Public Property EmailAddress As String
    Public Property Phone As String
    Public Property AddressType As String
    Public Property AddressLine1 As String
    Public Property AddressLine2 As String
    Public Property City As String
    Public Property StateProvince As String
    Public Property PostalCode As String
    Public Property AddressID As Integer
    Public Property AddressModifiedDate As DateTime
    Public Property CustomerModifiedDate As DateTime
End Class
```

```csharp
public class CustomerPresentationModel
{
    [Key]
    public int CustomerID { get; set; }
    public string FirstName { get; set; }
    public string LastName { get; set; }
    public string EmailAddress { get; set; }
    public string Phone { get; set; }
    public string AddressType { get; set; }
    public string AddressLine1 { get; set; }
    public string AddressLine2 { get; set; }
    public string City { get; set; }
    public string StateProvince { get; set; }
    public string PostalCode { get; set; }
    public int AddressID { get; set; }
    public DateTime AddressModifiedDate { get; set; }
    public DateTime CustomerModifiedDate { get; set; }
}
```

--------------------------------

### Declare Domain Context Namespace

Source: https://openriaservices.gitbook.io/openriaservices/ee707349/ee707363.md

Namespace declaration for the server project containing the domain context, replacing ExampleApplication.Web with your specific project name.

```xml
xmlns:domain="clr-namespace:ExampleApplication.Web"
```

--------------------------------

### Implement the FetchSovereigns method

Source: https://openriaservices.gitbook.io/openriaservices/ee707336/gg602754.md

Provides a method that returns a list of Sovereign entity instances.

```csharp
public List<Sovereign> FetchSovereigns()
        {
            List<Sovereign> sovereignList = new List<Sovereign>
            {
            new Sovereign()
                {UniqueId = 1, 
                 Name = "John", 
                 House = "Plantagenet", 
                 Dominion = "Angevin Empire", 
                 ReignStart = 1167, 
                 ReignEnd = 1216, 
                 Sobriquet = "Lackland"
                },
            new Sovereign()
                {UniqueId = 2, 
                 Name = "Charles", 
                 House = "Stuart", 
                 Dominion = "England, Scotland, & Ireland", 
                 ReignStart = 1625, 
                 ReignEnd = 1649, 
                 Sobriquet = "The Martyr"
                },
            new Sovereign()
                {UniqueId = 3, 
                 Name = "William", 
                 House = "Dunkeld", 
                 Dominion = "Scotland", 
                 ReignStart = 1165, 
                 ReignEnd = 1249, 
                 Sobriquet = "The Lion"
                },   
            new Sovereign()
                {UniqueId = 4, 
                 Name = "Elizabeth", 
                 House = "Tudor", 
                 Dominion = "England", 
                 ReignStart = 1555, 
                 ReignEnd = 1609, 
                 Sobriquet = "The Virgin Queen"
                },
            new Sovereign()
                {UniqueId = 5, 
                 Name = "Ivan", 
                 House = "Vasilyevich", 
                 Dominion = "Russia", 
                 ReignStart = 1533, 
                 ReignEnd = 1584, 
                 Sobriquet = "The Terrible"
                },
            new Sovereign()
                {UniqueId = 6, 
                 Name = "Charles", 
                 House = "Valois", 
                 Dominion = "France", 
                 ReignStart = 1380, 
                 ReignEnd = 1422, 
                 Sobriquet = "The Mad"
                }
            };
        return sovereignList;
        }
```

--------------------------------

### Implement ProfileWindow for user settings

Source: https://openriaservices.gitbook.io/openriaservices/ee707361/ee942451.md

A ChildWindow implementation that initializes a ComboBox with user preferences and saves updates to the WebContext.

```vbnet
Partial Public Class ProfileWindow
    Inherits ChildWindow

    Public Sub New()
        InitializeComponent()
        Dim userDefaultRows = WebContext.Current.User.DefaultRows.ToString()
        For Each cbi As ComboBoxItem In defaultRows.Items
            If (cbi.Content.ToString() = userDefaultRows) Then
                defaultRows.SelectedItem = cbi
                Exit For
            End If
        Next
    End Sub

    Private Sub OKButton_Click(ByVal sender As Object, ByVal e As RoutedEventArgs) Handles OKButton.Click
        Dim newSelection = Integer.Parse(defaultRows.SelectionBoxItem.ToString())
        If (newSelection <> WebContext.Current.User.DefaultRows) Then
            WebContext.Current.User.DefaultRows = newSelection
            WebContext.Current.Authentication.SaveUser(True)
        End If
        Me.DialogResult = True
    End Sub

    Private Sub CancelButton_Click(ByVal sender As Object, ByVal e As RoutedEventArgs) Handles CancelButton.Click
        Me.DialogResult = False
    End Sub

End Class
```

```csharp
public partial class ProfileWindow : ChildWindow
{
    public ProfileWindow()
    {
        InitializeComponent();
        string userDefaultRows = WebContext.Current.User.DefaultRows.ToString();
        foreach (ComboBoxItem cbi in defaultRows.Items)
        {
            if (cbi.Content.ToString() == userDefaultRows)
            {
                defaultRows.SelectedItem = cbi;
                break;
            }
        }
    }

    private void OKButton_Click(object sender, RoutedEventArgs e)
    {
        int newSelection = int.Parse(defaultRows.SelectionBoxItem.ToString());
        if (newSelection != WebContext.Current.User.DefaultRows)
        {
            WebContext.Current.User.DefaultRows = newSelection;
            WebContext.Current.Authentication.SaveUser(true);
        }
        this.DialogResult = true;
    }

    private void CancelButton_Click(object sender, RoutedEventArgs e)
    {
        this.DialogResult = false;
    }
}
```

--------------------------------

### Initialize DomainContext and Load Data

Source: https://openriaservices.gitbook.io/openriaservices/ee707336/hh556025.md

Logic to initialize the DomainContext and load data into the DataGrid, placed within the MainPage constructor.

```csharp
            ctx = new NWDomainContext();

            ctx.Load(ctx.GetProductsQuery());
            ctx.Load(ctx.GetCategoriesQuery());
            this.dataGrid1.ItemsSource = ctx.Products;
```

--------------------------------

### Initialize Reports Page Constructor

Source: https://openriaservices.gitbook.io/openriaservices/ee707361/ee942451.md

Initializes the page components and sets the visibility of the settings button based on the user's authentication status.

```csharp
public Reports()
{
    InitializeComponent();
    LoadReports();
    if (WebContext.Current.User.IsAuthenticated)
    {
        SettingsButton.Visibility = System.Windows.Visibility.Visible;
    }
}
```

--------------------------------

### Instantiate Context and Load Data

Source: https://openriaservices.gitbook.io/openriaservices/ee707336/ff713719.md

Initializes the OrganizationContext and loads employee data into the DataGrid.

```vbnet
Partial Public Class EmployeeList
    Inherits Page

    Dim _OrganizationContext As New OrganizationContext
    Public Sub New()
        InitializeComponent()
        Me.dataGrid1.ItemsSource = _OrganizationContext.Employees
        _OrganizationContext.Load(_OrganizationContext.GetEmployeesQuery())
    End Sub

    'Executes when the user navigates to this page.
    Protected Overrides Sub OnNavigatedTo(ByVal e As System.Windows.Navigation.NavigationEventArgs)

    End Sub
End Class
```

```csharp
public partial class EmployeeList : Page
{
    OrganizationContext _OrganizationContext = new OrganizationContext();
    public EmployeeList()
    {
        InitializeComponent();
        this.dataGrid1.ItemsSource = _OrganizationContext.Employees;
        _OrganizationContext.Load(_OrganizationContext.GetEmployeesQuery());
    }

    // Executes when the user navigates to this page.
    protected override void OnNavigatedTo(NavigationEventArgs e)
    {
    }
}
```

--------------------------------

### MainPage Implementation

Source: https://openriaservices.gitbook.io/openriaservices/ee707336/ee707376.md

Complete implementation of the MainPage class for loading and binding data.

```csharp
    namespace RIAServicesExample
    {
        public partial class MainPage : UserControl
        {
            private CustomerDomainContext _customerContext = new CustomerDomainContext();
            public MainPage()
            {
                InitializeComponent();

                LoadOperation<Customer> loadOp = this._customerContext.Load(this._customerContext.GetCustomersQuery());
                CustomerGrid.ItemsSource = loadOp.Entities;
            }
        }
    }
```

--------------------------------

### Implement User Authentication and Registration in VB.NET

Source: https://openriaservices.gitbook.io/openriaservices/ee707361/ee942451.md

Handles login, logout, and user registration operations using OpenRiaServices.Client.Authentication and RegistrationDomainContext. Requires appropriate UI controls to be defined in the corresponding XAML file.

```vbnet
Imports OpenRiaServices.Client.Authentication
Imports OpenRiaServices.Client
Imports System.ComponentModel.DataAnnotations

Partial Public Class Home
    Inherits Page

    Public Sub New()
        InitializeComponent()
    End Sub

    Protected Overrides Sub OnNavigatedTo(ByVal e As System.Windows.Navigation.NavigationEventArgs)
        SetControlVisibility(WebContext.Current.User.IsAuthenticated)
    End Sub

    Private Sub LoginButton_Click(ByVal sender As Object, ByVal e As RoutedEventArgs)
        Dim lp As LoginParameters = New LoginParameters(UserName.Text, Password.Password)
        WebContext.Current.Authentication.Login(lp, AddressOf Me.LoginOperation_Completed, Nothing)
        LoginButton.IsEnabled = False
        LoginResult.Text = ""
    End Sub

    Private Sub LoginOperation_Completed(ByVal lo As LoginOperation)
        If (lo.HasError) Then
            LoginResult.Text = lo.Error.Message
            LoginResult.Visibility = System.Windows.Visibility.Visible
            lo.MarkErrorAsHandled()
        ElseIf (lo.LoginSuccess = False) Then
            LoginResult.Text = "Login failed. Please check user name and password."
            LoginResult.Visibility = System.Windows.Visibility.Visible
        ElseIf (lo.LoginSuccess = True) Then
            SetControlVisibility(True)
        End If
        LoginButton.IsEnabled = True
    End Sub

    Private Sub SetControlVisibility(ByVal isAuthenticated As Boolean)
        If (isAuthenticated) Then
            LoginBorder.Visibility = System.Windows.Visibility.Collapsed
            RegisterBorder.Visibility = Windows.Visibility.Collapsed
            WelcomeText.Text = "Welcome " + WebContext.Current.User.Name
            WelcomeText.Visibility = System.Windows.Visibility.Visible
            LogoutButton.Visibility = System.Windows.Visibility.Visible
        Else
            LoginBorder.Visibility = System.Windows.Visibility.Visible
            RegisterBorder.Visibility = Windows.Visibility.Visible
            WelcomeText.Visibility = System.Windows.Visibility.Collapsed
            LogoutButton.Visibility = System.Windows.Visibility.Collapsed
        End If
    End Sub

    Private Sub LogoutButton_Click(ByVal sender As Object, ByVal e As RoutedEventArgs)
        WebContext.Current.Authentication.Logout(AddressOf Me.LogoutOperation_Completed, Nothing)
    End Sub

    Private Sub LogoutOperation_Completed(ByVal lo As LogoutOperation)
        If (Not (lo.HasError)) Then
            SetControlVisibility(False)
        Else
            Dim ew As ErrorWindow = New ErrorWindow("Logout failed.", "Please try logging out again.")
            ew.Show()
            lo.MarkErrorAsHandled()
        End If
    End Sub

    Private Sub RegisterButton_Click(ByVal sender As Object, ByVal e As RoutedEventArgs)
        RegisterButton.IsEnabled = False
        Dim context = New RegistrationDomainContext()
        Dim nu = New NewUser()
        Try
            nu.UserName = NewUsername.Text
            nu.Password = NewPassword.Password
            nu.Email = NewEmail.Text
            nu.ConfirmPassword = NewConfirmPassword.Password
            nu.RecordsToShow = Integer.Parse(DefaultRows.SelectionBoxItem.ToString())
            nu.SecurityQuestion = SecurityQuestion.Text
            nu.SecurityAnswer = SecurityAnswer.Text
            context.NewUsers.Add(nu)

            context.SubmitChanges(AddressOf RegisterUser_Completed, Nothing)
        Catch ve As ValidationException
            registerResult.Visibility = System.Windows.Visibility.Visible
            registerResult.Text = ve.Message
            RegisterButton.IsEnabled = True
        End Try
    End Sub

    Private Sub RegisterUser_Completed(ByVal so As SubmitOperation)
        If (so.HasError) Then
            Dim ew = New ErrorWindow("Registration failed.", "Please try registering again.")
            ew.Show()
            so.MarkErrorAsHandled()
        Else
            Dim lp = New LoginParameters(NewUsername.Text, NewPassword.Password)
            WebContext.Current.Authentication.Login(lp, AddressOf Me.LoginOperation_Completed, Nothing)
            NewUsername.Text = ""
            NewPassword.Password = ""
            NewConfirmPassword.Password = ""
            NewEmail.Text = ""
            DefaultRows.SelectedIndex = 0
            SecurityQuestion.Text = ""
            SecurityAnswer.Text = ""
        End If
        RegisterButton.IsEnabled = True
    End Sub
End Class
```

--------------------------------

### Load Data in Silverlight with VB.NET

Source: https://openriaservices.gitbook.io/openriaservices/ee707361/ee942449.md

Handles data loading and UI visibility based on user authentication status and roles.

```vbnet
        Private Sub LoadReports()
            If (WebContext.Current.User.IsAuthenticated) Then
                numberOfRows = WebContext.Current.User.DefaultRows
                AddHandler WebContext.Current.User.PropertyChanged, AddressOf User_PropertyChanged
                LoadRestrictedReports()
            Else
                CustomersGrid.Visibility = System.Windows.Visibility.Collapsed
                SalesOrdersGrid.Visibility = System.Windows.Visibility.Collapsed
            End If

            Dim loadProducts = context.Load(context.GetProductsQuery().Take(numberOfRows))
            ProductsGrid.ItemsSource = loadProducts.Entities
        End Sub

        Private Sub LoadRestrictedReports()
            Dim loadSales = context.Load(context.GetSalesOrderHeadersQuery().Take(numberOfRows))
            SalesOrdersGrid.ItemsSource = loadSales.Entities
            SalesOrdersGrid.Visibility = System.Windows.Visibility.Visible

            If (WebContext.Current.User.IsInRole("Managers")) Then
                Dim loadCustomers = context.Load(context.GetCustomersQuery().Take(numberOfRows))
                CustomersGrid.ItemsSource = loadCustomers.Entities
                CustomersGrid.Visibility = System.Windows.Visibility.Visible
            Else
                CustomersGrid.Visibility = System.Windows.Visibility.Collapsed
            End If
        End Sub

        Private Sub User_PropertyChanged(ByVal sender As Object, ByVal e As System.ComponentModel.PropertyChangedEventArgs)
            If (e.PropertyName = "DefaultRows") Then
                LoadReports()
            End If
        End Sub

        Private Sub Authentication_LoggedIn(ByVal sender As Object, ByVal e As Authentication.AuthenticationEventArgs)
            LoadReports()
        End Sub

        Private Sub Authentication_LoggedOut(ByVal sender As Object, ByVal e As Authentication.AuthenticationEventArgs)
            CustomersGrid.Visibility = System.Windows.Visibility.Collapsed
            SalesOrdersGrid.Visibility = System.Windows.Visibility.Collapsed
        End Sub
    End Class
```

--------------------------------

### Implement User Registration Logic

Source: https://openriaservices.gitbook.io/openriaservices/ee707361/ee942451.md

Handles the registration button click event to submit new user data and processes the completion of the registration operation.

```csharp
private void RegisterButton_Click(object sender, RoutedEventArgs e)
{
    RegisterButton.IsEnabled = false;
    RegistrationDomainContext context = new RegistrationDomainContext();
    NewUser nu = new NewUser();
    try
    {
        nu.UserName = NewUsername.Text;
        nu.Password = NewPassword.Password;
        nu.Email = NewEmail.Text;
        nu.ConfirmPassword = NewConfirmPassword.Password;
        nu.RecordsToShow = int.Parse(DefaultRows.SelectionBoxItem.ToString());
        nu.SecurityQuestion = SecurityQuestion.Text;
        nu.SecurityAnswer = SecurityAnswer.Text;
        context.NewUsers.Add(nu);

        context.SubmitChanges(RegisterUser_Completed, null);
    }
    catch (ValidationException ve)
    {
        registerResult.Visibility = System.Windows.Visibility.Visible;
        registerResult.Text = ve.Message;
        RegisterButton.IsEnabled = true;
    }
}

private void RegisterUser_Completed(SubmitOperation so)
{
    if (so.HasError)
    {
        ErrorWindow ew = new ErrorWindow("Registration failed.", "Please try registering again.");
        ew.Show();
        so.MarkErrorAsHandled();
    }
    else
    {
        LoginParameters lp = new LoginParameters(NewUsername.Text, NewPassword.Password);
        WebContext.Current.Authentication.Login(lp, this.LoginOperation_Completed, null);
        NewUsername.Text = "";
        NewPassword.Password = "";
        NewConfirmPassword.Password = "";
        NewEmail.Text = "";
        DefaultRows.SelectedIndex = 0;
        SecurityQuestion.Text = "";
        SecurityAnswer.Text = "";
    }
    RegisterButton.IsEnabled = true;
}
```

--------------------------------

### Implement OnCreated for DomainContext

Source: https://openriaservices.gitbook.io/openriaservices/ee707349/ee707345.md

Customizes the domain context initialization to automatically load data upon creation.

```vbnet
Imports OpenRiaServices.Client
Namespace Web
  Partial Public Class EmployeeDomainContext
    Inherits DomainContext
    Private Sub OnCreated()
      Me.Load(Me.GetEmployeesQuery())
    End Sub
  End Class
End Namespace
```

```csharp
using OpenRiaServices.Client;

namespace RIAServiceExample.Web
{
  public partial class EmployeeDomainContext : DomainContext
  {
    partial void OnCreated()
    {
      this.Load(this.GetEmployeesQuery());
    }
  }
}
```

--------------------------------

### Complete system.web Configuration

Source: https://openriaservices.gitbook.io/openriaservices/ee707361/ee942451.md

The combined configuration for authentication, roles, and profiles within the system.web element.

```xml
<system.web>
  <compilation debug="true" targetFramework="4.0" />
  <authentication mode="Forms"></authentication>
  <roleManager enabled="true"></roleManager>
  <profile enabled="true">
    <properties>
      <add type="System.Int32" defaultValue="10" name="DefaultRows"/>
    </properties>
  </profile>
</system.web>
```

--------------------------------

### Implement Profile Window Logic

Source: https://openriaservices.gitbook.io/openriaservices/ee707361/ee942449.md

Code-behind for a Silverlight ChildWindow to initialize the ComboBox with current user settings and save changes to the data source.

```vb
Imports System.Windows.Controls
Imports System.Windows

Partial Public Class ProfileWindow
    Inherits ChildWindow

    Public Sub New()
        InitializeComponent()

        Dim userDefaultRows = WebContext.Current.User.DefaultRows.ToString()
        For Each cbi As ComboBoxItem In defaultRows.Items
            If (cbi.Content.ToString() = userDefaultRows) Then
                defaultRows.SelectedItem = cbi
                Exit For
            End If
        Next
    End Sub

    Private Sub OKButton_Click(ByVal sender As Object, ByVal e As RoutedEventArgs) Handles OKButton.Click
        Dim newSelection = Integer.Parse(defaultRows.SelectionBoxItem.ToString())
        If (newSelection <> WebContext.Current.User.DefaultRows) Then
            WebContext.Current.User.DefaultRows = newSelection
            WebContext.Current.Authentication.SaveUser(True)
        End If
        Me.DialogResult = True
    End Sub

    Private Sub CancelButton_Click(ByVal sender As Object, ByVal e As RoutedEventArgs) Handles CancelButton.Click
        Me.DialogResult = False
    End Sub

End Class
```

--------------------------------

### Define NewUser class properties

Source: https://openriaservices.gitbook.io/openriaservices/ee707361/ee942451.md

Defines the data structure and validation rules for user registration.

```vbnet
Imports System.ComponentModel.DataAnnotations

Public Class NewUser

    <Key()> _
    <Required()> _
    <RegularExpression("^[a-zA-Z0-9_]*$", ErrorMessage:="Invalid user name. It must contain only alphanumeric characters")> _
    Public Property UserName As String

    <Key()> _
    <Required()> _
    <RegularExpression("^([\w-\.]+)@(([\d{1,3}\.\d{1,3}\.\d{1,3}\.)|(([\w-]+\.)+))([a-zA-Z]{2,4}|[\d{1,3}])(\]?)$", ErrorMessage:="Invalid email. An email must use the format username@mycompany.com")> _
    Public Property Email As String

    <Required()> _
    <RegularExpression("^.*[^a-zA-Z0-9].*$", ErrorMessage:="A password needs to contain at least one special character e.g. @ or #")> _
    <StringLength(50, MinimumLength:=7, ErrorMessage:="Invalid password. It must be contain at least 7 characters and no more than 50 characters.")> _
    Public Property Password As String

    <Required()> _
    <CustomValidation(GetType(RegistrationValidator), "IsPasswordConfirmed")> _
    Public Property ConfirmPassword As String

    <Range(1, 20)> _
    Public Property RecordsToShow As Integer

    <Required()> _
    Public Property SecurityQuestion As String

    <Required()> _
    Public Property SecurityAnswer As String
End Class
```

```csharp
using System;
using System.ComponentModel.DataAnnotations;

namespace ExampleNavigationApplication.Web
{
    public class NewUser
    {
        [Key]
        [Required()]
        [RegularExpression("^[a-zA-Z0-9_]*$", ErrorMessage="Invalid user name. It must contain only alphanumeric characters")]
        public string UserName { get; set; }

        [Key]
        [Required()]
        [RegularExpression(@"^([\w-\.]+)@(([\d{1,3}\.\d{1,3}\.\d{1,3}\.)|(([\w-]+\.)+))([a-zA-Z]{2,4}|[\d{1,3}])(\]?)$", ErrorMessage="Invalid email. An email must use the format username@mycompany.com")]
        public string Email { get; set; }

        [Required()]
        [RegularExpression("^.*[^a-zA-Z0-9].*$", ErrorMessage="A password needs to contain at least one special character e.g. @ or #")]
        [StringLength(50, MinimumLength = 7, ErrorMessage="Invalid password. It must be contain at least 7 characters and no more than 50 characters.")]
        public string Password { get; set; }

        [Required()]
        [CustomValidation(typeof(RegistrationValidator), "IsPasswordConfirmed")]
        public string ConfirmPassword { get; set; }

        [Range(1, 20)]
        public int RecordsToShow { get; set; }

        [Required()]
        public string SecurityQuestion { get; set; }

        [Required()]
        public string SecurityAnswer { get; set; }
    }
}
```

--------------------------------

### Retrieve and Filter Customers via DomainContext

Source: https://openriaservices.gitbook.io/openriaservices/ee707349/ee707370.md

Demonstrates filtering and sorting data using LINQ queries on a domain context, then loading the results into a DataGrid.

```vbnet
Partial Public Class MainPage
    Inherits UserControl

    Private _customerContext As New CustomerDomainContext

    Public Sub New()
        InitializeComponent()

        Dim query As EntityQuery(Of Customer)

        query = _
            From c In Me._customerContext.GetCustomersQuery() _
            Where c.Phone.StartsWith("583") _
            Order By c.LastName

        Dim loadOp = Me._customerContext.Load(query)
        CustomerGrid.ItemsSource = loadOp.Entities
    End Sub

End Class
```

```csharp
public partial class MainPage : UserControl
{
    private CustomerDomainContext _customerContext = new CustomerDomainContext();

    public MainPage()
    {
        InitializeComponent();
        EntityQuery<Customer> query = 
            from c in _customerContext.GetCustomersQuery()
            where c.Phone.StartsWith("583")
            orderby c.LastName
            select c;
        LoadOperation<Customer> loadOp = this._customerContext.Load(query);
        CustomerGrid.ItemsSource = loadOp.Entities;
    }
}
```

--------------------------------

### Configure Web.config

Source: https://openriaservices.gitbook.io/openriaservices/ee707336/ee707351.md

Update the Web.config file with connection strings and service model settings required for the domain service.

```xml
<configuration>
    <connectionStrings>
        <add name="AdventureWorksLT2008Entities" connectionString="metadata=res://*/Model1.csdl|res://*/Model1.ssdl|res://*/Model1.msl;provider=System.Data.SqlClient;provider connection string=&quot;Data Source=example;Initial Catalog=AdventureWorksLT2008;Integrated Security=True;MultipleActiveResultSets=True&quot;" providerName="System.Data.EntityClient" />
    </connectionStrings>
    <system.serviceModel>
        <serviceHostingEnvironment aspNetCompatibilityEnabled="true" />
    </system.serviceModel>
    <system.web>
        <compilation debug="true" targetFramework="4.0" />
    <httpModules>
        <add name="DomainServiceModule" type="System.Web.Ria.Services.DomainServiceHttpModule, System.Web.Ria, Version=4.0.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35" />
    </httpModules>
    </system.web>
    <system.webServer>
      <modules runAllManagedModulesForAllRequests="true"/>
    </system.webServer>

</configuration>
```

--------------------------------

### Implement Domain Service with Compositional Hierarchy

Source: https://openriaservices.gitbook.io/openriaservices/ee707348/ee707356/ee707346.md

A Domain Service implementation using LinqToEntitiesDomainService to manage SalesOrderHeader entities and their associated SalesOrderDetail entities.

```vbnet
<EnableClientAccess()>  _
Public Class OrderDomainService
    Inherits LinqToEntitiesDomainService(Of AdventureWorksLT_DataEntities)

    Public Function GetSalesOrders() As IQueryable(Of SalesOrderHeader)
        Return Me.ObjectContext.SalesOrderHeaders.Include("SalesOrderDetails")
    End Function

    Public Sub UpdateSalesOrder(ByVal currentSalesOrderHeader As SalesOrderHeader)
        Dim originalOrder As SalesOrderHeader = Me.ChangeSet.GetOriginal(currentSalesOrderHeader)

        If (currentSalesOrderHeader.EntityState = EntityState.Detached) Then
            If (IsNothing(originalOrder)) Then
                Me.ObjectContext.Attach(currentSalesOrderHeader)
            Else
                Me.ObjectContext.AttachAsModified(currentSalesOrderHeader, Me.ChangeSet.GetOriginal(currentSalesOrderHeader))
            End If
        End If

        For Each detail As SalesOrderDetail In Me.ChangeSet.GetAssociatedChanges(currentSalesOrderHeader, Function(o) o.SalesOrderDetails)
            Dim op As ChangeOperation = Me.ChangeSet.GetChangeOperation(detail)

            Select Case op
                Case ChangeOperation.Insert
                    If ((detail.EntityState = EntityState.Added) _
                    = False) Then
                        If ((detail.EntityState = EntityState.Detached) _
                                    = False) Then
                            Me.ObjectContext.ObjectStateManager.ChangeObjectState(detail, EntityState.Added)
                        Else
                            Me.ObjectContext.AddToSalesOrderDetails(detail)
                        End If
                    End If
                Case ChangeOperation.Update
                    Me.ObjectContext.AttachAsModified(detail, Me.ChangeSet.GetOriginal(detail))
                Case ChangeOperation.Delete
                    If (detail.EntityState = EntityState.Detached) Then
                        Me.ObjectContext.Attach(detail)
                    End If
                    Me.ObjectContext.DeleteObject(detail)
            End Select
        Next
    End Sub

    Public Sub DeleteSalesOrder(ByVal salesOrderHeader As SalesOrderHeader)
        If (salesOrderHeader.EntityState = EntityState.Detached) Then
            Me.ObjectContext.Attach(salesOrderHeader)
        End If

        Select Case salesOrderHeader.Status
            Case 1 ' in process
                Me.ObjectContext.DeleteObject(salesOrderHeader)
            Case 2, 3, 4 ' approved, backordered, rejected
                salesOrderHeader.Status = 6
            Case 5 ' shipped
                Throw New ValidationException("The order has been shipped and cannot be deleted.")
        End Select

    End Sub
End Class
```

--------------------------------

### Invoke Operation Execution and Completion Handling

Source: https://openriaservices.gitbook.io/openriaservices/ee707349/ee707370.md

Demonstrates calling an invoke operation and processing the result or errors within a completion callback.

```vbnet
Dim invokeOp As InvokeOperation(Of Integer)
invokeOp = customerContext.GetLocalTemperature(selectedPostalCode, AddressOf OnInvokeCompleted, Nothing)

Private Sub OnInvokeCompleted(ByVal invOp As InvokeOperation(Of Integer))
  If (invOp.HasError) Then
    MessageBox.Show(String.Format("Method Failed: {0}", invOp.Error.Message))
    invOp.MarkErrorAsHandled()
  Else
    result = invOp.Value
  End If
End Sub
```

```csharp
InvokeOperation<int> invokeOp = customerContext.GetLocalTemperature(selectedPostalCode, OnInvokeCompleted, null);

private void OnInvokeCompleted(InvokeOperation<int> invOp)
{
  if (invOp.HasError)
  {
    MessageBox.Show(string.Format("Method Failed: {0}", invOp.Error.Message));
    invOp.MarkErrorAsHandled();
  }
  else
  {
    result = invOp.Value;
  }
}
```

--------------------------------

### Define a basic query method in DomainService

Source: https://openriaservices.gitbook.io/openriaservices/ee707336/gg602754.md

Implement a method returning an IEnumerable collection to expose data to the client.

```csharp
        public IEnumerable<Sovereign> GetSovereigns()
        { 
            Sovereign sovereign = new Sovereign();
            return sovereign.FetchSovereigns();
        }
```

--------------------------------

### Implement AuthenticationDomainService and Custom User Class

Source: https://openriaservices.gitbook.io/openriaservices/ee707361/ee942451.md

Define the AuthenticationDomainService and extend the User class to include custom profile properties.

```vb
<EnableClientAccess()> _
Public Class AuthenticationDomainService
    Inherits AuthenticationBase(Of User)

End Class

Public Class User
    Inherits UserBase

    Public Property DefaultRows As Integer

End Class
```

```csharp
[EnableClientAccess]
public class AuthenticationDomainService : AuthenticationBase<User>
{
}

public class User : UserBase
{
    public int DefaultRows { get; set; }
}
```

--------------------------------

### Initialize Domain Context Variables

Source: https://openriaservices.gitbook.io/openriaservices/ee707348/ee707356/ff422034.md

Declare instances of the required domain contexts for data operations.

```vb
Private salesContext As New SalesDomainContext()
Private customerContext As New CustomerDomainContext()
```

```csharp
private SalesDomainContext salesContext = new SalesDomainContext();
private CustomerDomainContext customerContext = new CustomerDomainContext();
```

--------------------------------

### Accessing and Saving User Profile Properties

Source: https://openriaservices.gitbook.io/openriaservices/ee707361.md

Demonstrates updating a user property and persisting the change using the authentication service.

```vbnet
Private Sub OKButton_Click(ByVal sender As Object, ByVal e As RoutedEventArgs) Handles OKButton.Click
    Dim newSelection = Integer.Parse(defaultRows.SelectionBoxItem.ToString())
    If (newSelection <> WebContext.Current.User.DefaultRows) Then
        WebContext.Current.User.DefaultRows = newSelection
        WebContext.Current.Authentication.SaveUser(True)
    End If
    Me.DialogResult = True
End Sub
```

```csharp
private void OKButton_Click(object sender, RoutedEventArgs e)
{
    int newSelection = int.Parse(defaultRows.SelectionBoxItem.ToString());
    if (newSelection != WebContext.Current.User.DefaultRows)
    {
        WebContext.Current.User.DefaultRows = newSelection;
        WebContext.Current.Authentication.SaveUser(true);
    }
    this.DialogResult = true;
}
```

--------------------------------

### Load Data in Code-Behind

Source: https://openriaservices.gitbook.io/openriaservices/ee707336/ee707376.md

Instantiates the DomainContext and loads data into the DataGrid using Visual Basic or C#.

```vbnet
Imports System.Windows.Ria
Imports RIAServicesExample.Web

Partial Public Class MainPage
    Inherits UserControl

    Private _customerContext As New CustomerDomainContext

    Public Sub New()
        InitializeComponent()

        Dim loadOp = Me._customerContext.Load(Me._customerContext.GetCustomersQuery())
        CustomerGrid.ItemsSource = loadOp.Entities
    End Sub

End Class
```

```csharp
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 RIAServicesExample.Web;
using System.Windows.Ria;

namespace RIAServicesExample
{
    public partial class MainPage : UserControl
    {
        private CustomerDomainContext _customerContext = new CustomerDomainContext();

        public MainPage()
        {
            InitializeComponent();

            LoadOperation<Customer> loadOp = this._customerContext.Load(this._customerContext.GetCustomersQuery());
            CustomerGrid.ItemsSource = loadOp.Entities;
        }
    }
}
```
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