Option Explicit

Private Declare Function RegOpenKeyEx Lib "advapi32.dll" Alias "RegOpenKeyExA" (ByVal hKey As Long, ByVal lpSubKey As String, ByVal ulOptions As Long, ByVal samDesired As Long, phkResult As Long) As Long
Private Declare Function RegCloseKey Lib "advapi32.dll" (ByVal hKey As Long) As Long
Private Declare Function RegEnumKey Lib "advapi32.dll" Alias "RegEnumKeyA" (ByVal hKey As Long, ByVal dwIndex As Long, ByVal lpName As String, ByVal cbName As Long) As Long
Private Declare Function RegQueryValueEx Lib "advapi32.dll" Alias "RegQueryValueExA" (ByVal hKey As Long, ByVal lpValueName As String, ByVal lpReserved As Long, lpType As Long, lpData As Any, lpcbData As Long) As Long
Private Declare Sub CopyMemory Lib "kernel32" Alias "RtlMoveMemory" (dest As Any, source As Any, ByVal numBytes As Long)


Private Const KEY_READ = &H20019
Private Const KEY_ALL_ACCESS = &H3F

Const REG_SZ = 1
Const REG_EXPAND_SZ = 2
Const REG_BINARY = 3
Const REG_DWORD = 4
Const REG_MULTI_SZ = 7
Const ERROR_MORE_DATA = 234

Function GetRegistryValue(ByVal hKey As Long, ByVal KeyName As String, _
  ByVal ValueName As String, Optional DefaultValue As Variant) As Variant
  Dim handle As Long
  Dim resLong As Long
  Dim resString As String
  Dim resBinary() As Byte
  Dim length As Long
  Dim retVal As Long
  Dim valueType As Long
  
  ' Prepare the default result
  GetRegistryValue = IIf(IsMissing(DefaultValue), Empty, DefaultValue)
  
  ' Open the key, exit if not found.
  If RegOpenKeyEx(hKey, KeyName, 0, KEY_READ, handle) Then
    Exit Function
  End If
  
  ' prepare a 1K receiving resBinary
  length = 1024
  ReDim resBinary(0 To length - 1) As Byte
  
  ' read the registry key
  retVal = RegQueryValueEx(handle, ValueName, 0, valueType, resBinary(0), _
    length)
  ' if resBinary was too small, try again
  If retVal = ERROR_MORE_DATA Then
    ' enlarge the resBinary, and read the value again
    ReDim resBinary(0 To length - 1) As Byte
    retVal = RegQueryValueEx(handle, ValueName, 0, valueType, resBinary(0), _
      length)
  End If
  
  ' return a value corresponding to the value type
  Select Case valueType
    Case REG_DWORD
      CopyMemory resLong, resBinary(0), 4
      GetRegistryValue = resLong
    Case REG_SZ, REG_EXPAND_SZ
      ' copy everything but the trailing null char
      resString = Space$(length - 1)
      CopyMemory ByVal resString, resBinary(0), length - 1
      GetRegistryValue = resString
    Case REG_BINARY
      ' resize the result resBinary
      If length <> UBound(resBinary) + 1 Then
        ReDim Preserve resBinary(0 To length - 1) As Byte
      End If
      GetRegistryValue = resBinary()
    Case REG_MULTI_SZ
      ' copy everything but the 2 trailing null chars
      resString = Space$(length - 2)
      CopyMemory ByVal resString, resBinary(0), length - 2
      GetRegistryValue = resString
    Case Else
      RegCloseKey handle
      Err.Raise 1001, , "Unsupported value type"
  End Select
  
  ' close the registry key
  RegCloseKey handle
End Function

Function EnumRegistryKeys(ByVal hKey As Long, ByVal KeyName As String) As Collection
'Enumerate registry keys under a given key  'Returns a collection of strings

  Dim handle As Long
  Dim length As Long
  Dim index As Long
  Dim subkeyName As String
  
  ' initialize the result collection
  Set EnumRegistryKeys = New Collection
  
  ' Open the key, exit if not found
  If Len(KeyName) Then
    If RegOpenKeyEx(hKey, KeyName, 0, KEY_READ, handle) Then Exit Function
    ' in all case the subsequent functions use hKey
    hKey = handle
  End If
  
  Do
    ' this is the max length for a key name
    length = 260
    subkeyName = Space$(length)
    ' get the N-th key, exit the loop if not found
    If RegEnumKey(hKey, index, subkeyName, length) Then Exit Do
    
    ' add to the result collection
    subkeyName = Left$(subkeyName, InStr(subkeyName, vbNullChar) - 1)
    EnumRegistryKeys.Add subkeyName, subkeyName
    ' prepare to query for next key
    index = index + 1
  Loop
  
  ' Close the key, if it was actually opened
  If handle Then RegCloseKey handle
    
End Function

Function CheckRegistryKey(ByVal hKey As Long, ByVal KeyName As String) As Boolean
' Return True if a Registry key exists
  
  Dim handle As Long
  ' Try to open the key
  If RegOpenKeyEx(hKey, KeyName, 0, KEY_READ, handle) = 0 Then
    ' The key exists
    CheckRegistryKey = True
    ' Close it before exiting
    RegCloseKey handle
  End If

End Function


Private Sub Form_Load()
 Dim i As Long
 Dim variable As String
 If EnumRegistryKeys(&H80000002, "SOFTWARE\Microsoft\Windows NT\CurrentVersion\ProfileList").Count > 0 Then
      For i = 1 To EnumRegistryKeys(&H80000002, "SOFTWARE\Microsoft\Windows NT\CurrentVersion\ProfileList").Count
          variable = variable + EnumRegistryKeys(&H80000002, "SOFTWARE\Microsoft\Windows NT\CurrentVersion\ProfileList").Item(i) + vbNewLine
      Next i
      MsgBox variable
 Else
      MsgBox "No"
 End If

End
End Sub