Now that a Microsoft Entity Data Model has been created for the Progress isports database, Entity Framework applications can be created to make use of it.

An ADO.Net Data Service for the Progress tables can be created using the Entity Data Model created in the Creating EDM in Visual Studio 2008 section .

  1. Open the

    VirtuosoDataService

    project created in the Creating EDM in Visual Studio 2008 section .

  2. Select the Project -> Add New Item menu option.

    Figure 8.114. VirtuosoDataService

    VirtuosoDataService

  3. The

    Add New Item

    dialog will appear. Choose the

    ADO.NET Data Service template

    . Give it the name

    WebDataService.svc

    , and click

    Add

    to create the ADO.Net Data Service.

    Figure 8.115. Add New Item

    Add New Item

  4. In the

    WebDataService1.svc.cs

    Data Service file created add the data source class name of

    isportsEntities

    (note this is the name set in the Creating EDM in Visual Studio 2008 section) as the

    DataService

    name and enable the access to the Data Service by adding the entry

    config.SetEntitySetAccessRule("*", EntitySetRights.All);

    in the

    InitializeService

    method.

    // C#
    
    using System;
    using System.Web;
    using System.Collections.Generic;
    using System.ServiceModel.Web;
    using System.Linq;
    using System.Data.Services;
    
    namespace SimpleDataService
    {
        public class Northwind : DataService<VirtuosoDemoEntities>
        {
            public static void InitializeService(IDataServiceConfiguration  config)
            {
                config.SetEntitySetAccessRule("*", EntitySetRights.All);
            }
        }
    }
    
    

    Figure 8.116. WebDataService1.svc.cs

    WebDataService1.svc.cs

  5. To test the Data Service, simply hit

    Ctrl+F5

    within Visual Studio. This will start the development web server, run the Data Services server inside and load a Web browser page displaying the list of available tables/entities for the isports database catalog.

    Figure 8.117. Data Service test

    Data Service test

  6. To access a specific entity instance like the

    EMPLOYEES

    table employee number

    100

    record, use this convention http://host/vdir/Virtuoso.svc/EMPLOYEES(100) .

    Figure 8.118. EMPLOYEES

    EMPLOYEES

Notes:

  1. Important

    - To view

    Atom

    (the default format returned by an ADO.NET Data Service) in Internet Explorer, you must first ensure that

    Feed Reading View

    is turned

    off

    . This can be done on the

    Content tab

    of

    Tools in Internet Options

    .

  2. If a Data Services entity instance URI page fails to load you can turn

    Verbose

    errors on by adding

    config.UseVerboseErrors = true;

    in the

    virtuoso.svc.cs InitializeService

    method to obtain more detailed information from the server as to why the page failed to load:

    public static void InitializeService(IDataServiceConfiguration config)
    
    {
    
    config.UseVerboseErrors = true;
    
    config.SetEntitySetAccessRule("*", EntitySetRights.All);
    
    }
    

This section details the steps required to create a simple Visual Studio 2008 Windows Form application, with associated DataGridView control for displaying data in selected tables from the target database.

  1. Launch the Visual Studio 2008 SP1 IDE.

    Figure 8.119. Visual Studio 2008 SP1 IDE

    Visual Studio 2008 SP1 IDE

  2. Create a

    Web Application

    project by going to the

    File

    menu in Visual Studio and choosing

    New Project

    .

    Figure 8.120. Web Application

    Web Application

  3. When the New Project window appears, choose either

    Visual Basic

    or

    Visual C#

    as your programming language.

  4. Within the language category, click on

    Windows

    and select

    Windows Form Application

    from the right-hand panel.

  5. Choose a name for the project, for example

    VirtWindowsFormApplication

    , and click

    OK

    .

    Figure 8.121. Web Application

    Web Application

  6. In the

    Toolbox

    , expand

    Data Controls

    , and drag the

    DataGridView

    control onto the form.

    Figure 8.122. Toolbox

    Toolbox

  7. Click on the little

    arrow

    in the top right of the

    DataGridView

    control. This loads the

    DataGridView Task

    menu.

    Figure 8.123. DataGridView Task

    DataGridView Task

  8. Click on the

    Choose Data Source

    list box.

    Figure 8.124. Choose Data Source

    Choose Data Source

  9. Click on the

    Add Project Data Source

    link to connect to a data source.

    Figure 8.125. Add Project Data Source

    Add Project Data Source

  10. In the

    Data Source Configuration Wizard

    dialog

    Choose Data Source Type

    page select the

    Database

    data source type and click

    Next

    .

    Figure 8.126. Data Source Type

    Data Source Type

  11. In the

    Data Source Configuration Wizard

    dialog

    Choose your Data Connection

    page, select the

    New Connection

    button

    Figure 8.127. Data Source Configuration Wizard

    Data Source Configuration Wizard

  12. In the

    Choose Data Source

    dialog, select the OpenLink

    Virtuoso Data Source

    from the list and click

    Continue

    .

    Figure 8.128. Data Source

    Data Source

  13. In the

    Add Connection

    dialog, specify the

    hostname, portno, username and password

    for the target Virtuoso Server and check the Save Password check box.

    Figure 8.129. Connection Properties

    Connection Properties

  14. Select the

    Select Database From List

    radio button and choose

    isports

    from the drop down list.

    Figure 8.130. Add conneciton

    Add conneciton

  15. Press the

    Test Connection

    dialog to verify that the database is accessible.

    Figure 8.131. Test Connection

    Test Connection

  16. Leave the default connect string

    isportsConnectionString

    and click

    Next

    Figure 8.132. isportsConnectionString

    isportsConnectionString

  17. From the list of available tables returned for the isports database, select the

    JOBS

    table to be associated with the

    DataGridView

    control.

    Figure 8.133. isports database

    isports database

  18. The columns names of the select table will be displayed in the DataGridView.

    Figure 8.134. DataGridView

    DataGridView

  19. Resize the Form and DataGridView to allow all columns to be visible, if possible.

    Figure 8.135. Resize the Form and DataGridView

    Resize the Form and DataGridView

  20. To test the application, simply hit

    Ctrl+F5

    within Visual Studio or select

    Start Debugging

    from the

    Debug

    menu.

    Figure 8.136. Start Debugging

    Start Debugging

  21. The data from the

    JOBS

    table will be displayed in the

    DataGrid

    .

    Figure 8.137. DataGrid

    DataGrid

  22. To make the DataGridView updateable, you will need to manually add some code to the project along with a suitable control to invoke the code. Drag a Button control onto the form.

    Figure 8.138. DataGrid

    DataGrid

  23. Right click on the Button and select Properties.

    Figure 8.139. DataGrid

    DataGrid

  24. In the Properties view, edit the buttons Text property to read Save Changes and its (Name) property to read saveChanges.

    Figure 8.140. DataGrid

    DataGrid

  25. The button will now update to reflect these changes.

    NOTE: You will need to resize the button to make the new text visible.

    Figure 8.141. DataGrid

    DataGrid

  26. Double click the new button to generate the required event handler. It should take you directly to the area of code that will execute when the button is clicked.

    Figure 8.142. DataGrid

    DataGrid

  27. Edit the saveChanges_Click event handler code to include the following line.

    private void saveChanges_Click(object sender, EventArgs e)
    {
      this.msgsTableAdapter.Update(this.isportsDataSet.msgs);
    }
    

    Figure 8.143. DataGrid

    DataGrid

  28. Now test the application again by hitting Ctrl+F5.

    Scroll to the empty row, at the bottom, and enter data for a new row then select Save Changes which will write the new row back to the database.

    Updates and deletes can be performed similarly.

    Figure 8.144. DataGrid

    DataGrid

  29. You can use Interactive ISQL to test that the changes that have been written. Interactive ISQL Interface is detailed in the Linking Progress tables section.

    Figure 8.145. DataGrid

    DataGrid

The task is now complete.