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EnumRegistryValues – Retrieve all values under a Registry key

EnumRegistryValues – Retrieve all values under a Registry key

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 LongPrivate Declare Function RegCloseKey Lib "advapi32.dll" (ByVal hKey As Long) As _    LongPrivate Declare Function RegEnumValue Lib "advapi32.dll" Alias "RegEnumValueA" _    (ByVal hKey As Long, ByVal dwIndex As Long, ByVal lpValueName As String, _    lpcbValueName As Long, ByVal lpReserved As Long, lpType As Long, _    lpData As Any, lpcbData As Long) As LongPrivate Declare Sub CopyMemory Lib "kernel32" Alias "RtlMoveMemory" (dest As _    Any, source As Any, ByVal numBytes As Long)Const REG_SZ = 1Const REG_EXPAND_SZ = 2Const REG_BINARY = 3Const REG_DWORD = 4Const REG_MULTI_SZ = 7Const ERROR_MORE_DATA = 234Const KEY_READ = &H20019  ' ((READ_CONTROL Or KEY_QUERY_VALUE Or                           ' KEY_ENUMERATE_SUB_KEYS Or KEY_NOTIFY) And (Not                           ' SYNCHRONIZE))' Enumerate values under a given registry key'' returns a collection, where each element of the collection' is a 2-element array of Variants:'    element(0) is the value name, element(1) is the value's valueFunction EnumRegistryValues(ByVal hKey As Long, ByVal KeyName As String) As _    Collection    Dim handle As Long    Dim index As Long    Dim valueType As Long    Dim name As String    Dim nameLen As Long    Dim resLong As Long    Dim resString As String    Dim dataLen As Long    Dim valueInfo(0 To 1) As Variant    Dim retVal As Long        ' initialize the result    Set EnumRegistryValues = 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 cases, subsequent functions use hKey        hKey = handle    End If        Do        ' this is the max length for a key name        nameLen = 260        name = Space$(nameLen)        ' prepare the receiving buffer for the value        dataLen = 4096        ReDim resBinary(0 To dataLen - 1) As Byte                ' read the value's name and data        ' exit the loop if not found        retVal = RegEnumValue(hKey, index, name, nameLen, ByVal 0&, valueType, _            resBinary(0), dataLen)                ' enlarge the buffer if you need more space        If retVal = ERROR_MORE_DATA Then            ReDim resBinary(0 To dataLen - 1) As Byte            retVal = RegEnumValue(hKey, index, name, nameLen, ByVal 0&, _                valueType, resBinary(0), dataLen)        End If        ' exit the loop if any other error (typically, no more values)        If retVal Then Exit Do                ' retrieve the value's name        valueInfo(0) = Left$(name, nameLen)                ' return a value corresponding to the value type        Select Case valueType            Case REG_DWORD                CopyMemory resLong, resBinary(0), 4                valueInfo(1) = resLong            Case REG_SZ, REG_EXPAND_SZ                ' copy everything but the trailing null char                resString = Space$(dataLen - 1)                CopyMemory ByVal resString, resBinary(0), dataLen - 1                valueInfo(1) = resString            Case REG_BINARY                ' shrink the buffer if necessary                If dataLen < UBound(resBinary) + 1 Then                    ReDim Preserve resBinary(0 To dataLen - 1) As Byte                End If                valueInfo(1) = resBinary()            Case REG_MULTI_SZ                ' copy everything but the 2 trailing null chars                resString = Space$(dataLen - 2)                CopyMemory ByVal resString, resBinary(0), dataLen - 2                valueInfo(1) = resString            Case Else                ' Unsupported value type - do nothing        End Select                ' add the array to the result collection        ' the element's key is the value's name        EnumRegistryValues.Add valueInfo, valueInfo(0)                index = index + 1    Loop       ' Close the key, if it was actually opened    If handle Then RegCloseKey handle        End Function

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