Reading from and Writing to the Registry Using the Microsoft.Win32 Namespace (Visual Basic)

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Although My.Computer.Registry should cover your basic needs when programming against the registry, you can also use the Registry and RegistryKey classes in the Microsoft.Win32 namespace of the .NET Framework.

Keys in the Registry Class

The Registry class supplies the base registry keys that can be used to access subkeys and their values. The base keys themselves are read-only. The following table lists and describes the seven keys exposed by the Registry class.

Key

Description

ClassesRoot

Defines the types of documents and the properties associated with those types.

CurrentConfig

Contains hardware configuration information that is not user-specific.

CurrentUser

Contains information about the current user preferences, such as environmental variables.

DynData

Contains dynamic registry data, such as that used by Virtual Device Drivers.

LocalMachine

Contains five subkeys (Hardware, SAM, Security, Software, and System) that hold the configuration data for the local computer.

PerformanceData

Contains performance information for software components.

Users

Contains information about the default user preferences.
Security noteSecurity Note

It is more secure to write data to the current user (CurrentUser) than to the local computer (LocalMachine). A condition that's typically referred to as "squatting" occurs when the key you are creating was previously created by another, possibly malicious, process. To prevent this from occurring, use a method, such as GetValue, that returns Nothing if the key does not already exist.

Reading a Value from the Registry

The following code shows how to read a string from HKEY_CURRENT_USER.

Dim regVersion As Microsoft.Win32.RegistryKey
Dim keyValue = "Software\\Microsoft\\TestApp\\1.0"
regVersion = Microsoft.Win32.Registry.CurrentUser.OpenSubKey(keyValue, False)
Dim intVersion As Integer = 0
If regVersion IsNot Nothing Then
    intVersion = regVersion.GetValue("Version", 0)
    regVersion.Close()
End If

The following code reads, increments, and then writes a string to HKEY_CURRENT_USER.

Dim regVersion = Microsoft.Win32.Registry.CurrentUser.OpenSubKey(
                  "SOFTWARE\\Microsoft\\TestApp\\1.0", True)
If regVersion Is Nothing Then
    ' Key doesn't exist; create it.
    regVersion = Microsoft.Win32.Registry.CurrentUser.CreateSubKey(
                 "SOFTWARE\\Microsoft\\TestApp\\1.0")
End If

Dim intVersion As Integer = 0
If regVersion IsNot Nothing Then
    intVersion = regVersion.GetValue("Version", 0)
    intVersion = intVersion + 1
    regVersion.SetValue("Version", intVersion)
    regVersion.Close()
End If

See Also

Tasks

Troubleshooting: Manipulating the Registry (Visual Basic)

Reference

SystemException

ApplicationException

RegistryProxy

Concepts

Structured Exception Handling Overview for Visual Basic

Common Registry Tasks (Visual Basic)

Security and the Registry (Visual Basic)

Reading from and Writing to the Registry Using My (Visual Basic)