What Is the .NET Framework?

This section answers the question, What is the .NET Framework? in a way that addresses the special needs of Visual Basic and VBA developers who create applications with Access databases. To you, the .NET Framework offers a new way of working that can vastly increase the uses of your Access database applications. I will cover the special benefits the .NET Framework offers for Access developers in the next section. This section aims to give an overview of the .NET Framework that will equip you for the journey through the rest of this chapter.

The .NET Framework is a software development environment that embraces Access databases and other kinds of databases. Rather than working directly with the .NET Framework, developers use their favorite programming language. For Visual Basic and VBA programmers, Visual Basic .NET is a natural choice. This programming language works much like Microsoft Visual Basic 6.0, but it contains special features, many of which let you take advantage of the .NET Framework.

The .NET Framework through Microsoft Visual Studio .NET makes available several templates for starting different kinds of solutions. Access developers regularly create solutions for a local area network (LAN) or even a single workstation. The Windows Application template serves this kind of solution especially well. After opening the template, you will feel right at home with a toolbox that lets you drag controls onto a form that opens for you automatically. The form is an instance of the Windows Form class. While the form is tailored for the .NET Framework, it works very much like Visual Basic or Access forms. For example, you can still use the familiar code-behind form development model that you already know and love. The Windows Application template is the one to use when your solution can benefit from exploiting fully the Microsoft Windows operating system s rich user interface features.

In creating applications with Visual Basic .NET or any .NET programming language, Access database developers will need a component to connect to their data. While you are currently programming either ActiveX Data Objects (ADO) or Data Access Objects (DAO) with Visual Basic or VBA to connect with Access databases, the .NET Framework offers ADO.NET for this purpose. ADO and ADO.NET share few specific features. In fact, the new capabilities of ADO.NET enable you to expand the maximum number of concurrent users of your Access databases. (I will explain why later in this chapter when I focus specifically on ADO.NET.)

Another advantage to the .NET Framework is the ease with which you can permit users to tap into your databases via the Web, such as with ASP.NET or with XML Web services. Just as ADO.NET is the component that handles data, ASP.NET is the component that handles interacting with an intranet, an extranet, or the Internet. You can think of ASP.NET as your Web development tool since ASP.NET is easier and more powerful than its predecessor ”ASP (Active Server Pages). Access developers will appreciate the many new controls for binding to data. Even more important is the capability to code Web applications with a code-behind page model. This ASP.NET feature works just like the code- behind form feature in Visual Basic and VBA. It isolates control layout issues from code that controls user interactivity. The new capability relieves developers of having to write VBScript and HTML code on the same Web page.

ASP.NET also offers the capability to create XML Web services based on Access databases. An XML Web service lets two computers exchange data even if they are running different operating systems; clients running applications on UNIX can now connect to your Access applications running on Windows. This communication goes both ways. In addition, Access developers can extend the life of existing Access applications by making their contents available as an XML Web service. Access developers can tap the benefits of these and other XML Web services with the ASP.NET component of the .NET Framework. ASP.NET manages all the plumbing for implementing an XML Web service. After you learn a few simple concepts, XML Web services are a snap to program with Visual Basic .NET.

Note  

Some readers may be wondering what happened to data access pages. Microsoft introduced this technology as a way of simplifying the creation of Web applications for Access developers. With data access pages, developers can graphically arrange data-bound controls on a Web page. The programming interface for data access pages is similar to Visual InterDev. Microsoft replaced the programming interface with the release of the .NET Framework. This traditional Web development environment requires you to program user interactivity by mixing a scripting language such as VBScript and HTML on the same page. ASP.NET lets you code Web applications with Visual Basic .NET, not some derivative language such as VBScript, and it does not force you to intermingle Visual Basic .NET and HTML on the same page.