Visual Studio Orcas, due for release at the end of 2007, promises numerous improvements for Visual Basic, a data query called the Language Integrated Query (LINQ), a new Entity Framework for ADO.NET and updated tools for ASP.NET AJAX and Office 2007 development.
This two-part series examines ten of the IDE's new features as they were explained during sessions at DevConnections 2007. This article looks at the improvements to the IDE and the aforementioned ADO.NET Entity Framework. Part 2 looks at what's new in Visual Basic 9 and LINQ; as you will see, these two concepts are closely related.
Visual Studio Orcas is billed as the design surface for the .NET Framework 3.5, which itself is the merger of the .NET 3.0 toolset introduced earlier this year with updated versions of ASP.NET, ADO.NET, Visual Basic, C# and the CLR.
At the same time, though, Orcas allows developers to work backwards and develop specifically for .NET 2.0 or 3.0. In the words of Jeff King, program manager on the Visual Studio team, the tool and the framework are decoupled: "It really buys you freedom."
Once a framework version has been selected, Visual Studio Orcas will enable the reference features that are appropriate for that version of the framework. (In other words, don't try using LINQ in a .NET 2.0 application.)
N-tier application development
An n-tier application is spread among any number of different systems, typically a service layer, an access layer and a business logic layer. With such a model, it is easy to share validation logic between entities, said Young Joo, a Visual Basic program manager.
Unfortunately, developing such applications in Visual Studio 2005 is "pretty much impossible," Joo said, because a dataset and the code that connects it to a database are in the same file. The change in Visual Studio Orcas is subtle but important, as the table and the dataset now reside in different layers.
An improved designer
King described the Visual Studio 2005 designer as little more the Internet Explorer renderer turned into an editor. To improve upon this, the Visual Studio group turned to Expression, the Microsoft product suite for Web designers.
The new designer allows developers to apply styles in line, with an existing class, with a new class or with Internet Explorer. "We default manually nowadays," King said. In addition, changes such as margins and paddings around images can be applied to rules and not just individually. This also makes for cleaner CSS files.
Finally, the designer offers a split view, so developers can look at source code and design simultaneously. This is a response to the growing trend of development using two monitors, King said.
ASP.NET AJAX and VSTO for Office 2007
Right now, developers aiming to build cutting edge Web applications have to download the ASP.NET AJAX framework, and those who want to develop for Office 2007 have to download Visual Studio 2005 Tools for Office Second Edition.
The ADO.NET Entity Framework
The biggest changes to ADO.NET revolve around its Entity Framework, which, unfortunately, is now slated to be released quite a while after Visual Studio 2008. This framework consists of a conceptual layer, which fits between an application's logical database layer and its object layer, and the Entity Data Model, said Julia Lerman, consultant and owner of The Data Farm.
Run the Entity Data Model Wizard in Visual Studio Orcas and the output is three files -- a conceptual model that talks to object classes, a logical model that the relational database talks to, and map between the conceptual and logical models.
Within the conceptual layer, one finds entity types bundled into sets, associations that define the relationship between entities, and sets of associations. The information in this layer will handle the back and forth with SQL Server without touching data access code, Lerman said.
Once entities have been created, developers can use the either CreateQuery or new LINQ to Entities query to retrieve entity objects, data records or anonymous types, Lerman said.