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DragonSteve
Dec 26th, 2000, 09:10 AM
Hi,

How can I retrieve the default value out of the registry?

THANX

Chris
Dec 26th, 2000, 09:49 AM
Default value?

DragonSteve
Dec 26th, 2000, 09:51 AM
Yes,

The "(Default)" string value in the rightpane of the regediter.

Chris
Dec 26th, 2000, 09:55 AM
I don't think you can get that value.

Dec 26th, 2000, 12:29 PM
Yes you can. All you have to do is pass a blank string for the parameter that you would normally fill in with a value.

Dec 26th, 2000, 12:32 PM
Here some registry code you can use.

Add to a Module

Declare Function RegCloseKey Lib "advapi32.dll" (ByVal HKEY As Long) As Long
Declare Function RegCreateKey Lib "advapi32.dll" Alias "RegCreateKeyA" (ByVal HKEY As Long, ByVal lpSubKey As String, phkResult As Long) As Long
Declare Function RegDeleteKey Lib "advapi32.dll" Alias "RegDeleteKeyA" (ByVal HKEY As Long, ByVal lpSubKey As String) As Long
Declare Function RegDeleteValue Lib "advapi32.dll" Alias "RegDeleteValueA" (ByVal HKEY As Long, ByVal lpValueName As String) As Long
Declare Function RegOpenKey Lib "advapi32.dll" Alias "RegOpenKeyA" (ByVal HKEY As Long, ByVal lpSubKey As String, phkResult As Long) As Long
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
Declare Function RegSetValueEx Lib "advapi32.dll" Alias "RegSetValueExA" (ByVal HKEY As Long, ByVal lpValueName As String, ByVal Reserved As Long, ByVal dwType As Long, lpData As Any, ByVal cbData 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_PERFORMANCE_DATA = &H80000004
Public Const REG_SZ = 1

Function RegQueryStringValue(ByVal HKEY As Long, ByVal strValueName As String)
Dim lResult As Long
Dim lValueType As Long
Dim strBuf As String
Dim lDataBufSize As Long

On Error GoTo 0
lResult = RegQueryValueEx(HKEY, strValueName, 0&, lValueType, ByVal 0&, lDataBufSize)
If lResult = ERROR_SUCCESS Then
If lValueType = REG_SZ Then
strBuf = String(lDataBufSize, " ")
lResult = RegQueryValueEx(HKEY, strValueName, 0&, 0&, ByVal strBuf, lDataBufSize)
If lResult = ERROR_SUCCESS Then
RegQueryStringValue = StripTerminator(strBuf)
End If
End If
End If
End Function

Public Function GetSettingEx(HKEY As Long, sPath As String, sValue As String)
Dim KeyHand&
Dim datatype&
Call RegOpenKey(HKEY, sPath, KeyHand&)
GetSettingEx = RegQueryStringValue(KeyHand&, sValue)
Call RegCloseKey(KeyHand&)
End Function

Function StripTerminator(ByVal strString As String) As String
Dim intZeroPos As Integer

intZeroPos = InStr(strString, Chr$(0))
If intZeroPos > 0 Then
StripTerminator = Left$(strString, intZeroPos - 1)
Else
StripTerminator = strString
End If
End Function

Public Sub SaveSettingEx(HKEY As Long, sPath As String, sValue As String, sData As String)
Dim KeyHand As Long
Call RegCreateKey(HKEY, sPath, KeyHand)
Call RegSetValueEx(KeyHand&, sValue, 0, REG_SZ, ByVal sData, Len(sData))
Call RegCloseKey(KeyHand&)
End Sub


Usage:

'Save a Value to the Registry
SaveSettingEx HKEY_CURRENT_USER, "Software\Myapp", "Testing", "Hello"


'Get a value from the Registry
Retval = GetSettingEx(HKEY_CURRENT_USER, "Software\Myapp", "Testing")
Print Retval

'Get the (default) value from the Registry
Retval = GetSettingEx(HKEY_CURRENT_USER, "Software\Myapp", "")
Print Retval

Chris
Dec 26th, 2000, 12:38 PM
Thanks Magatron, Juz learn somethings new from you. :))

DragonSteve
Dec 27th, 2000, 02:47 AM
THANX Megatron for the answer.

jtaylorlb
Jan 2nd, 2001, 04:13 AM
Hey,
I know the problems been solved, but if you are using the example provided in vb-world.net or using raw API you can use vbNullString as the key name and it will return the default value.
:)

Jan 2nd, 2001, 10:04 AM
DragonSteve: You're welcome.


jtaylorlb: You can do that with the above code too.