This article is part three of a four part series on the ADO.NET Entity Framework. This article discusses the new Entity Data Source control which was introduced as part of the Visual Studio.NET 2008 SP1 release.
Data controls are those that can be bound to data from external data sources. These data sources may include databases, XML files or flat files. ASP.NET 2.0 introduced some data source controls with a powerful data binding technique that eliminated the need to write lengthy code for binding data to data controls.
In ASP.NET the term Data Binding implies binding the controls to data retrieved from a data source and providing a read or write connectivity between these controls and the data that they are bound to.
The Entity Data Source control is an example of a data control that is included as part of the Visual Studio 2008 SP1 release and can be used to bind data retrieved from an Entity Data Model to the data bound controls of ASP.NET. If Visual Studio 2008 SP1 is installed, the EntityDataSource control can be seen listed in the Data section of the toolbox.
If the EntityDataSource control is not in the toolbox, follow these steps:
1. Right-click on the Toolbox and select the Choose Items option as shown in the following figure:
2. From the list of the components displayed, scroll down to locate the EntityDataSource in the .NET Framework Components tab. This is the first component selected in the below figure:
3. Select the checkbox next to the EntityDataSource component and click on OK. The ADO.NET Entity Data Source control is now added to the toolbox as shown in the following figure:
If the EntityDataSource component is not listed in the list of the components displayed in the Choose Toolbox Items window, it has to be added manually. To do this, click on the Browse button in the Choose Toolbox Items window, locate the System.Web.Entity.dll in the folder where Microsoft .NET Framework 3.5 has been installed and click OK.
The final article in this series explores how to implement an application using the entity framework.