The document outlines the migration process for .NET applications to version 4.5, emphasizing the importance of project compatibility and environment readiness. It describes the version history of the .NET framework, detailing components and features of each version, especially the differences in compatibility and updates. Additionally, it provides instructions on checking installed .NET framework versions and updates through the Windows registry.

1. Migration of .net Application
Muthu Swamy S
ms@deepbiz.net
+91 98861 97840
October 20, 2012 .Net Migration
Version and Dependencies
Migration of .net Application
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2. Scope
Upgrading your earlier version of .NET applications to .Net Framework 4.5 is easy by opening
the project in Visual Studio 2012. If your project was created in an earlier version, the Project
Compatibility dialog box automatically opens.
However, some changes in the .NET Framework require changes to your code. You may also
want to take advantage of functionality that is new in the .NET Framework 4.5. Making these
types of changes to your application for a new version of the .NET Framework is typically
referred to as migration. If your application does not have to be migrated, you can run it in the
.NET Framework 4.5 without recompiling it.
You have to consider Application Compatibility and Version Compatibility during the migration.
Before start doing the migration you have to ensure the environment readiness for Version and
Dependencies of .NET Framework.
The purpose of this article is to explain how to check the available .NET Frameworks Version
and Dependencies in the System.
.NET Frameworks Version and Dependencies
Each version of the .NET Framework contains the common language runtime (CLR) as its core
component, and includes additional components such as the base class libraries and other
managed libraries. This article describes the key components of the .NET Framework by version,
provides information about the underlying CLR versions and associated development
environments, and identifies the versions that are installed by the Windows operating system
as indicated in the picture.
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3. Version History
The .NET Framework
versions 2.0, 3.0, and 3.5
are built with the same
version of the CLR (CLR
2.0). These versions
represent successive layers
of a single installation. Each
version is built incrementally on top of the earlier .NET Framework versions. It is not possible
to run versions 2.0, 3.0, and 3.5 side by side on a computer. When you install the .NET
Framework 3.5 SP1, you get the 2.0 and 3.0 layers automatically. However, the .NET
Framework 4 ends this layering approach. Starting with the .NET Framework 4, you can use in-
process side-by-side hosting to run multiple versions of the CLR in a single process. Apps that
were built for versions 2.0, 3.0, and 3.5 can all run on version 3.5, but they will not work on
version 4 or later.
The .NET Framework 4.5 is an in-place update that replaces the .NET Framework 4 on your
computer. After you install this update, your .NET Framework 4 apps should continue to run
without requiring recompilation. However, some changes in the .NET Framework may require
changes to your app code.
Features and IDE
NET Introduced Description
Framework with IDE
version
1.0 Visual Studio Contained the first version of the CLR and the first
.NET version of the base class libraries.
1.1 Visual Studio Included updates to ASP.NET and ADO.NET. This
.NET 2003 version was subsequently updated twice, with Service
Pack 1 (SP1) and SP2. This version also introduced
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4. side-by-side execution, which enables apps on a single
computer to run against multiple versions of the CLR.
2.0 Visual Studio Introduced a new version of the CLR with additions to
2005 the base class libraries, including generics, generic
collections, and significant additions to ASP.NET. This
version was updated with SP1 and SP2.
3.0 Visual Studio This version is essentially .NET Framework 2.0 with
2005 the addition of Windows Presentation Foundation
(WPF), Windows Communications Foundation (WCF),
Windows Workflow Foundation (WF), and CardSpace.
It was updated with SP1 and SP2.
3.5 Visual Studio Added new features such as AJAX-enabled websites
2008 and LINQ. The SP1 update added Dynamic Data, and
a small set of additional enhancements.
4 Visual Studio Included a new version of the CLR, expanded base
2010 class libraries, and new features such as the Managed
Extensibility Framework (MEF), dynamic language
runtime (DLR), and code contracts.
4.5 Visual Studio Includes an updated version of the CLR, support for
2012 building Windows Store apps, and updates to WPF,
WCF, WF, and ASP.NET.
.NET Framework Versions
You can find out the version numbers in the system using registry editor [regedit.exe] from the
windows registry. The installed versions are listed under the NDP subkey at
HKEY_LOCAL_MACHINESOFTWAREMicrosoftNET Framework SetupNDP
You can test whether the .NET Framework 4.5 or the .NET Framework 4 is installed by checking
the HKEY_LOCAL_MACHINESOFTWAREMicrosoftNET Framework SetupNDPv4Full subkey
in the registry for a DWORD value named Release. The existence of this DWORD indicates that
the .NET Framework 4.5 has been installed on that computer. The value of Release is a version
number. To determine if the final release version of the .NET Framework 4.5 is installed, check
for a value that is equal to or greater than 378389 as shown in the picture.
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5. The following code programmatically determines the versions of the .NET Framework that are
installed on a computer. You must have administrative credentials to run this example.
[Download Code here]
Read the Registry key from Microsoft.Win32 API using RegistryKey as shown here.
RegistryKey ndpKey = RegistryKey.OpenBaseKey(RegistryHive.LocalMachine,
RegistryView.Registry32).OpenSubKey(@"SOFTWAREMicrosoftNET Framework SetupNDP")
It will provide you the result as,
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6. .NET Framework Updates
You can read the framework updates from
HKEY_LOCAL_MACHINESOFTWAREWow6432NodeMicrosoftUpdates using the code
RegistryKey baseKey = RegistryKey.OpenBaseKey(RegistryHive.LocalMachine,
RegistryView.Registry32).OpenSubKey(@"SOFTWAREMicrosoftUpdates")
Once you run the code, the output shows the available .NET Framework updates in the system as shown in the
picture.
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7. Dot Net Framework Availability Checker Utilitty
The code demonstrates the .Net Frameworks Versions and their updates in the system. You
can download the code from here:
https://docs.google.com/open?id=0BxWxKlOt68qYbzBqa3dFcDVMQXM .
Setup file from here : https://docs.google.com/open?id=0BxWxKlOt68qYVjl5d0dOMGtsa0E
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