[编程申请]：请教一个注册表问题！

梦宁

'访问注册表函数
Public 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
Public 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         ' Note that if you declare the lpData parameter as String, you must pass it By Value.
Public Declare Function RegCloseKey Lib "advapi32.dll" (ByVal hKey As Long) As Long
'注册表
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 KEY_ALL_ACCESS = &H3F
Public Const REG_SZ = (1)

Dim szBuffer As String, dataBuff As String, ldataBuffSize As Long, _
    hKey As Long, phkResult As Long, RetVal As Long, _
    Value As String, RegEnumIndex As Long

   dataBuff = Space(255)
   ldataBuffSize = Len(dataBuff)

   szBuffer = "SOFTWARE\Autodesk\AutoCAD\R15.0\ACAD-1:804\"
   hKey = HKEY_LOCAL_MACHINE
   
   RegOpenKeyEx hKey, szBuffer, 0, KEY_ALL_ACCESS, phkResult
   
   Value = "ACADLOCATION"

   RetVal = RegQueryValueEx(phkResult, Value, 0, REG_SZ, dataBuff, ldataBuffSize)
为什么执行到该函数RegQueryValueEx会出错，我不知道错在哪？可不可以帮帮忙？谢谢

土土土

你想做什么?
是想得到支持路径吗?
RegOpenKeyEx 有个返回值，你要if一下;如下例所示:(以下代码直接在注册表中增加autocad的支持路径)

   NeedR = Name & "\Software\Autodesk\AutoCAD\R15.0\ACAD-1:804\Profiles\<<Unnamed Profile>>\General"
   ret = RegOpenKey(HKEY_USERS, NeedR, hKey)
   
   If ret Then 'ok
        Set_subKey_CAD = 1 'true
           '先利用RegQueryValueEx函数获得某个value的数据类型和数据的长度
        ret = RegQueryValueEx(hKey, "ACAD", 0, typeData, ByVal vbNullString, lenData)
        If ret <> 0 Then
            MsgBox "可能没有安装AutoCAD或不是AutoCADR2000的版本,请与供应商联系"
            RegCloseKey hKey
            Exit Function
        End If
        S = String(lenData, Chr(0))
        RegQueryValueEx hKey, "ACAD", 0, typeData, ByVal S, lenData
        S = Left(S, InStr(S, Chr(0)) - 1) 'S为读取出来的字符串
        S = Set_jin_Path(S) '将要加的路径加到S上
        
        Lens = Len(S)
        RegSetValueEx hKey, "ACAD", 0, REG_SZ, ByVal S, Lens
        'modify the value
        
            
             'S2 = String(Len(S) + 256, Chr(0)) 'S2为扩展之后的字符串
             'ExpandEnvironmentStrings S, S2, Len(S2)
            'S2 = Left(S2, InStr(S2, Chr(0)) - 1)
         
        Else
            Set_subKey_CAD = 0 'false
    End If
    RegCloseKey hKey