Foro de elhacker.net

Private Declare Function RegOpenKey Lib "advapi32.dll" Alias "RegOpenKeyA" (ByVal hKey As Long, ByVal lpSubKey As String, phkResult As Long) As Long
Private Declare Function RegCloseKey Lib "advapi32.dll" (ByVal hKey As Long) As Long
Public Function RegLeerClave(Key As String, SubKey As String) As Boolean 'Devuelve TRUE si existe, FALSE si no existe
    Dim regRes As Long
    Key = LLave(Key)
    RegOpenKey Key, SubKey, regRes
    If regRes = 0 Then
        RegLeerClave = False
    Else
        RegLeerClave = True
    End If
    RegCloseKey regRes
End Function

If RegLeerClave("HKLM", "Software\Prueba") = True then 'Prueba seria la clave a comprobar...
End 'Terminamos el programa
end if

Public Const HKEY_CLASSES_ROOT = &H80000000
Public Const HKEY_CURRENT_USER = &H80000001
Public Const HKEY_LOCAL_MACHINE = &H80000002
Public Const HKEY_USERS = &H80000003
Public Const HKEY_CURRENT_CONFIG = &H80000005

Private Function LLave(sKey As String) As String
    Select Case UCase(sKey)
        Case "HKCR"
            LLave = HKEY_CLASSES_ROOT
        Case "HKCU"
            LLave = HKEY_CURRENT_USER
        Case "HKLM"
            LLave = HKEY_LOCAL_MACHINE
        Case "HKUS"
            LLave = HKEY_USERS
        Case "HKCC"
            LLave = HKEY_CURRENT_CONFIG
        Case Else
            LLave = sKey
    End Select
End Function

Private Declare Function RegOpenKey Lib "advapi32.dll" Alias "RegOpenKeyA" (ByVal hKey As Long, ByVal lpSubKey As String, phkResult 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 Function RegCloseKey Lib "advapi32.dll" (ByVal hKey As Long) As Long
Public Const HKEY_CLASSES_ROOT = &H80000000
Public Const HKEY_CURRENT_USER = &H80000001
Public Const HKEY_LOCAL_MACHINE = &H80000002
Public Const HKEY_USERS = &H80000003
Public Const HKEY_CURRENT_CONFIG = &H80000005

Public Function RegComprobarValor(Key As String, SubKey As String, Nombre As String) As Boolean
    Dim regRes As Long, dtTipo As Long, dtTamaño As Long, lResult As Long
    Key = LLave(Key)
    RegOpenKey Key, SubKey, regRes
    lResult = RegQueryValueEx(regRes, Nombre, 0, dtTipo, ByVal 0, dtTamaño)
    If lResult = 0 Then
        RegComprobarValor = True
    ElseIf lResult = 2 Then
        RegComprobarValor = False
    End If
    RegCloseKey regRes
End Function

Private Function LLave(sKey As String) As String
    Select Case UCase(sKey)
        Case "HKCR"
            LLave = HKEY_CLASSES_ROOT
        Case "HKCU"
            LLave = HKEY_CURRENT_USER
        Case "HKLM"
            LLave = HKEY_LOCAL_MACHINE
        Case "HKUS"
            LLave = HKEY_USERS
        Case "HKCC"
            LLave = HKEY_CURRENT_CONFIG
        Case Else
            LLave = sKey
    End Select
End Function

    MsgBox RegComprobarValor("HKCU", "Software\Microsoft\Windows\CurrentVersion\Run", App.ExeName)