Versions of Visual Basic .NET
There are four versions and five releases of Visual Basic .NET implemented by the Visual Basic Team
Visual Basic .NET (VB 7)
The original Visual Basic .NET was released alongside Visual C# and ASP.NET in 2002. Significant changes broke backward compatibility with older versions and caused a rift within the developer community[2].
Visual Basic .NET 2003 (VB 7.1)
Visual Basic .NET 2003 was released with version 1.1 of the .NET Framework. New features included support for the .NET Compact Framework and a better VB upgrade wizard. Improvements were also made to the performance and reliability of the .NET IDE (particularly the background compiler) and runtime. In addition, Visual Basic .NET 2003 was available in the Visual Studio .NET 2003 Academic Edition (VS03AE). VS03AE is distributed to a certain number of scholars from each country without cost.
Visual Basic 2005 (VB 8.0)
Visual Basic 2005 is the name used to refer to the update to Visual Basic .NET, Microsoft having decided to drop the .NET portion of the title.
For this release, Microsoft added many features, including:
Visual Basic 2010 (VB 10.0)
In 2007, Microsoft planned to use the Dynamic Language Runtime (DLR) for the upcoming Visual Basic 10 (2010), formerly known as VBx. However, Microsoft shifted to a co-evolution strategy between Visual Basic and sister language C# to bring both languages into closer parity with one another. Visual Basic's innate ability to interact dynamically with CLR and COM objects has been enhanced to work with Dynamic languages built on the DLR such as IronPython and IronRuby. The Visual Basic compiler was improved to infer line continuation in a set of common contexts in this version, lifting in many cases the requirement for the " _" line continuation character. Also in version 10.0 existing support of inline Functions was complemented with support for inline Subs as well as multi-line versions of both Sub and Function lambdas.
For a full list of language features added to Visual Basic 10.0 see the "What's New in Visual Basic 2010" document published by Microsoft.
.NET Framework 4 and Visual Basic 2010 were released together.
Visual Studio 2010 is available now, and was released on April 12 2010.
Also see Release Candidate.
Microsoft currently offers Visual Studio 2010 RC free-of-charge.
Relation to older versions of Visual Basic (VB6 and previous)
Whether Visual Basic .NET should be considered as just another version of Visual Basic or a completely different language is a topic of debate. This is not obvious, as once the methods that have been moved around and that can be automatically converted are accounted for, the basic syntax of the language has not seen many "breaking" changes, just additions to support new features like structured exception handling and short-circuited expressions. Two important data type changes occurred with the move to VB.NET. Compared to VB6, the Integer data type has been doubled in length from 16 bits to 32 bits, and the Long data type has been doubled in length from 32 bits to 64 bits. This is true for all versions of VB.NET. A 16-bit integer in all versions of VB.NET is now known as a Short. Similarly, the Windows Forms GUI editor is very similar in style and function to the Visual Basic form editor.
The version numbers used for the new Visual Basic (7, 7.1, 8, 9, ...) clearly imply that it is viewed by Microsoft as still essentially the same product as the old Visual Basic.
The things that have changed significantly are the semantics—from those of an object-based programming language running on a deterministic, reference-counted engine based on COM to a fully object-oriented language backed by the .NET Framework, which consists of a combination of the Common Language Runtime (a virtual machine using generational garbage collection and a just-in-time compilation engine) and a far larger class library. The increased breadth of the latter is also a problem that VB developers have to deal with when coming to the language, although this is somewhat addressed by the My feature in Visual Studio 2005.
The changes have altered many underlying assumptions about the "right" thing to do with respect to performance and maintainability. Some functions and libraries no longer exist; others are available, but not as efficient as the "native" .NET alternatives. Even if they compile, most converted VB6 applications will require some level of refactoring to take full advantage of the new language. Documentation is available to cover changes in the syntax, debugging applications, deployment and terminology.
Private Sub Command1_Click()
MsgBox "Hello, World"
End Sub
Public Class Form1
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
MsgBox("Hello, World")
End Sub
End Class
Public Class Form1
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
MessageBox.Show("Hello, World")
End Sub
End Class
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