How to look for a registry key? 32/64 bit

Question

How to look for a registry key? I need to look from both 32 and 64 bit systems with 3 diffrent GUID's. I need to return the one it found the InstallLocation in to a TextBox. I have made the following code. Tho i don't know if it's actually usable. I am a beginner at this. Please help.

Imports Microsoft.Win32
Imports System.Net
Imports System

Public Class Form1

    Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
        Dim Is64Bit As Boolean

        Is64Bit = String.IsNullOrEmpty(Environment.GetEnvironmentVariable("PROCESSOR_ARCHITEW6432"))

        If Not Is64Bit Then
            Try
                Dim rk32_1 As RegistryKey
                rk32_1 = Registry.LocalMachine.OpenSubKey("SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\{1EAC1D02-C6AC-4FA6-9A44-96258C37C812EU}_is1")
                Dim il_rk32_1 As String = rk32_1.GetValue("InstallLocation").ToString

            Catch ex As Exception

            End Try
            Try
                Dim rk32_2 As RegistryKey
                rk32_2 = Registry.LocalMachine.OpenSubKey("SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\{1EAC1D02-C6AC-4FA6-9A44-96258C37C812NA}_is1")
                Dim il_rk32_2 As String = rk32_2.GetValue("InstallLocation").ToString

            Catch ex As Exception

            End Try
            Try
                Dim rk32_3 As RegistryKey
                rk32_3 = Registry.LocalMachine.OpenSubKey("SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\{1EAC1D02-C6AC-4FA6-9A44-96258C37C812RU}_is1")
                Dim il_rk32_3 As String = rk32_3.GetValue("InstallLocation").ToString

            Catch ex As Exception

            End Try
        End If

        If Is64Bit Then
            Try
                Dim rk64_1 As RegistryKey
                rk64_1 = Registry.LocalMachine.OpenSubKey("SOFTWARE\Wow6432Node\Microsoft\Windows\CurrentVersion\Uninstall\{1EAC1D02-C6AC-4FA6-9A44-96258C37C812EU}_is1")
                Dim il_rk64_1 As String = rk64_1.GetValue("InstallLocation").ToString

            Catch ex As Exception

            End Try
            Try
                Dim rk64_2 As RegistryKey
                rk64_2 = Registry.LocalMachine.OpenSubKey("SOFTWARE\Wow6432Node\Microsoft\Windows\CurrentVersion\Uninstall\{1EAC1D02-C6AC-4FA6-9A44-96258C37C812NA}_is1")
                Dim il_rk64_2 As String = rk64_2.GetValue("InstallLocation").ToString

            Catch ex As Exception

            End Try
            Try
                Dim rk64_3 As RegistryKey
                rk64_3 = Registry.LocalMachine.OpenSubKey("SOFTWARE\Wow6432Node\Microsoft\Windows\CurrentVersion\Uninstall\{1EAC1D02-C6AC-4FA6-9A44-96258C37C812RU}_is1")
                Dim il_rk64_3 As String = rk64_3.GetValue("InstallLocation").ToString

            Catch ex As Exception

            End Try
        End If

    End Sub

End Class

Answer 1

In order to access application configuration installed from a .reg file, I had to write the following function:

Public Const RegRoot As String = "Software\MyApp\"

Function ReadFromRegister(ByRef FieldToRead As String) As String
    ReadFromRegister = ""
    Dim MyReg As RegistryKey = RegistryKey.OpenBaseKey(RegistryHive.LocalMachine, RegistryView.Registry64)
    If MyReg Is Nothing Then
        End
    End If

    Dim MySubReg As RegistryKey = MyReg.OpenSubKey(RegRoot)
    If MySubReg Is Nothing Then
        End
    End If

    ReadFromRegister = MySubReg.GetValue(FieldToRead)
    MySubReg.Close()
    MyReg.Close()

End Function

Note that the function OpenBaseKey is introduced from Framework 4 on.

Answer 2

Firstly, keep in mind that if the program is compiled as x86, the (IntPtr.Size * 8) will always return 32 (if this is an issue, I do have a class that can get the OS version regardless of how the exe is compiled)

I'd recommend using the following :

Private Sub Form1_Load(ByVal sender As Object, ByVal e As EventArgs) Handles MyBase.Load
    ' Check if the OS is 64 bit
    Dim Is64Bit As Boolean = ((IntPtr.Size * 8) = 64)

    Dim UninstallPath As String = "SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\"

    If Is64Bit Then
        UninstallPath = UninstallPath.Insert(8, "\Wow6432Node")
    End If

    Dim il_rk32_1 As String = Nothing
    Dim il_rk32_2 As String = Nothing
    Dim il_rk32_3 As String = Nothing

    Try
        Dim rk32_1 As RegistryKey = Registry.LocalMachine.OpenSubKey(UninstallPath & "{1EAC1D02-C6AC-4FA6-9A44-96258C37C812EU}_is1")

        If rk32_1 IsNot Nothing Then
            Dim Val As Object = rk32_1.GetValue("InstallLocation")

            If Val IsNot Nothing Then
                il_rk32_1 = Val.ToString
            End If
        End If

    Catch ex As Exception

    End Try

    If String.IsNullOrEmpty(il_rk32_1) Then
        il_rk32_1 = "C:\Games\World_of_Tanks\"
    End If

    Me.TextBox1.Text = il_rk32_1


    Try
        Dim rk32_2 As RegistryKey = Registry.LocalMachine.OpenSubKey(UninstallPath & "{1EAC1D02-C6AC-4FA6-9A44-96258C37C812NA}_is1")

        If rk32_2 IsNot Nothing Then
            Dim Val As Object = rk32_2.GetValue("InstallLocation")

            If Val IsNot Nothing Then
                il_rk32_2 = Val.ToString
            End If
        End If

    Catch ex As Exception

    End Try

    If String.IsNullOrEmpty(il_rk32_2) Then
        il_rk32_2 = "C:\Games\World_of_Tanks\"
    End If

    Me.TextBox2.Text = il_rk32_2


    Try
        Dim rk32_3 As RegistryKey = Registry.LocalMachine.OpenSubKey(UninstallPath & "{1EAC1D02-C6AC-4FA6-9A44-96258C37C812RU}_is1")

        If rk32_3 IsNot Nothing Then
            Dim Val As Object = rk32_3.GetValue("InstallLocation")

            If Val IsNot Nothing Then
                il_rk32_3 = Val.ToString
            End If
        End If

    Catch ex As Exception

    End Try

    If String.IsNullOrEmpty(il_rk32_3) Then
        il_rk32_3 = "C:\Games\World_of_Tanks\"
    End If

    Me.TextBox3.Text = il_rk32_3

End Sub

Edit:

I've changed the above code to accomedate the OP's question (in the comments)

Answer 3

I didn't looked too much at your code 'cause you did the opposite checks. Wow64 refers to 32-Bit applications on 64-Bit machine.

From Wikipedia :

WoW64 (Windows 32-bit on Windows 64-bit)

The WoW64 subsystem also handles other key aspects of running 32-bit applications. It is involved in managing the interaction of 32-bit applications with the Windows components such as the Registry, which has distinct keys for 64-bit and 32-bit applications. For example HKEY_LOCAL_MACHINE\Software\Wow6432Node is the 32-bit equivalent of HKEY_LOCAL_MACHINE\Software (although 32-bit applications are not aware of this redirection). Some Registry keys are mapped from 64-bit to their 32-bit equivalents, while others have their contents mirrored, depending on the edition of Windows.

PS: Just to notice it, the same thing happens for System32 and SysWOW64 windows directories.

UPDATE:

Just an easy way to retrieve whether the OS is x64 (instead of getting a Environment variable PROCESSOR_ARCHITEW6432 which could be faked in a x86 OS):

' Get OS Architecture
' ( By Elektro)
'
' Usage Examples :
' Dim OSArchitecture As Architecture = GetOSArchitecture()
' MsgBox(OSArchitecture.ToString)
'
''' <summary>
''' Determines whether the OS is 32 or 64 Bits.
''' </summary>
''' <returns>
''' The return value could be: 
''' '32' for 32-Bit OS (x86)
''' '64' for 64-Bit OS (x64)
''' </returns>
Private Function GetOSArchitecture() As Architecture

    Return [Enum].Parse(GetType(Architecture),
                        Runtime.InteropServices.Marshal.SizeOf(GetType(IntPtr)) * 8)

End Function

''' <summary>
''' Indicates the possible processor architectures.
''' </summary>
Private Enum Architecture As Integer

    ''' <summary>
    ''' 32-Bit
    ''' </summary>
    x86 = 32

    ''' <summary>
    ''' 64-Bit
    ''' </summary>
    x64 = 64

End Enum