Registry

[Rebis]

Anyone know how to start an application by accessing the registry for its associated file types?

[Chris]

Hi! Rebis, this what I did in the pass few days. May be it can give you some hints..

'Copy this code into a Basic Module file

Option Explicit
'WIN32API Costant
Public Const REG_SZ = 1                         ' Unicode nul terminated string
Public Const REG_BINARY = 3                     ' Free form binary
Public Const REG_DWORD = 4                      ' 32-bit number

Public Const HKEY_CLASSES_ROOT = &H80000000
Public Const HKEY_CURRENT_CONFIG = &H80000005
Public Const HKEY_CURRENT_USER = &H80000001
Public Const HKEY_DYN_DATA = &H80000006
Public Const HKEY_LOCAL_MACHINE = &H80000002
Public Const HKEY_PERFORMANCE_DATA = &H80000004
Public Const HKEY_USERS = &H80000003

Public Const ERROR_SUCCESS = 0&

'WIN32 API declaration
Public Declare Function RegOpenKey Lib "advapi32.dll" Alias "RegOpenKeyA" (ByVal hKey As Long, ByVal lpSubKey As String, phkResult As Long) As Long
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 RegCloseKey Lib "advapi32.dll" (ByVal hKey As Long) As Long

Public Declare Function RegCreateKey Lib "advapi32.dll" Alias "RegCreateKeyA" (ByVal hKey As Long, ByVal lpSubKey As String, phkResult As Long) As Long
Public Declare Function RegDeleteKey Lib "advapi32.dll" Alias "RegDeleteKeyA" (ByVal hKey As Long, ByVal lpSubKey As String) As Long

Public 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         ' Note that if you declare the lpData parameter as String, you must pass it By Value.
Public Declare Function RegDeleteValue Lib "advapi32.dll" Alias "RegDeleteValueA" (ByVal hKey As Long, ByVal lpValueName As String) 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.

Private hCurKey As Long

Public Function DELETE_REG_STRING(ByVal hKey As Long, ByVal lpSubKey As String, ByVal lpString As String) As Long
On Error GoTo ErrHandle
    'Data validation
    If hKey = 0 Or lpSubKey = "" Or lpString = "" Then GoTo ErrHandle
    'Open the given hkey + SubKey
    If RegOpenKey(hKey, lpSubKey, hCurKey) = ERROR_SUCCESS Then
        'Delete the given String from given hkey + SubKey
        If RegDeleteValue(hCurKey, lpString) = ERROR_SUCCESS Then
            DELETE_REG_STRING = 1
        Else
            DELETE_REG_STRING = 0
        End If
    Else
        DELETE_REG_STRING = 0
    End If
    RegCloseKey hCurKey
Exit Function
ErrHandle:
    DELETE_REG_STRING = 0
End Function

Public Function GET_STRING_VALUE(ByVal hKey As Long, ByVal lpSubKey As String, ByVal lpString As String, ByVal dwType As Long) As Variant
On Error GoTo ErrHandle
    'Data validation
    If hKey = 0 Or lpSubKey = "" Or lpString = "" Then GoTo ErrHandle
    
    'Open the given hkey + subkey
    If RegOpenKey(hKey, lpSubKey, hCurKey) = ERROR_SUCCESS Then
        'Retrieve the given string value
        Select Case dwType
        Case REG_SZ
            Dim strBuff As String
            strBuff = String(255, Chr(0))
            
            If RegQueryValueEx(hCurKey, lpString, 0, dwType, ByVal strBuff, Len(strBuff)) = ERROR_SUCCESS Then
                GET_STRING_VALUE = Left(strBuff, InStr(1, strBuff, Chr(0), vbTextCompare))
            Else
                GET_STRING_VALUE = ""
            End If
        Case REG_BINARY
            Dim strData As Long
            
            If RegQueryValueEx(hCurKey, lpString, 0, dwType, strData, Len(strData)) = ERROR_SUCCESS Then
                GET_STRING_VALUE = strData
            Else
                GET_STRING_VALUE = ""
            End If
        Case REG_DWORD
            Dim strDWORD As String
            strDWORD = String(255, Chr(0))
            
            If RegQueryValueEx(hCurKey, lpString, 0, dwType, ByVal strDWORD, Len(strDWORD)) = ERROR_SUCCESS Then
                GET_STRING_VALUE = Left(strDWORD, InStr(1, strDWORD, Chr(0), vbTextCompare))
            Else
                GET_STRING_VALUE = ""
            End If
        End Select
    Else
        GET_STRING_VALUE = ""
    End If
    RegCloseKey hCurKey
    
    Exit Function
ErrHandle:
    GET_STRING_VALUE = ""
End Function
Public Function CREATE_REG_KEY(ByVal hKey As Long, ByVal lpSubKey As String) As Long
On Error GoTo ErrHandle
    'Data validation
    If hKey = 0 Or lpSubKey = "" Then GoTo ErrHandle
    If RegCreateKey(hKey, lpSubKey, hCurKey) = ERROR_SUCCESS Then
        CREATE_REG_KEY = 1
    Else
        CREATE_REG_KEY = 0
    End If
    RegCloseKey hCurKey
    Exit Function
    
ErrHandle:
    CREATE_REG_KEY = 0
End Function

Public Function DELETE_REG_KEY(ByVal hKey As Long, ByVal lpSubKey As String) As Long
On Error GoTo ErrHandle
    'Data validation
    If hKey = 0 Or lpSubKey = "" Then GoTo ErrHandle
    If RegDeleteKey(hKey, lpSubKey) = ERROR_SUCCESS Then
        DELETE_REG_KEY = 1
    Else
        DELETE_REG_KEY = 0
    End If
    Exit Function
   
ErrHandle:
    DELETE_REG_KEY = 0
End Function

Public Function CREATE_REG_STRING(ByVal hKey As Long, ByVal lpSubKey As String, ByVal lpString As String, ByVal dwType As Long, ByVal lpData As String) As Long
On Error GoTo ErrHandle
    'Data validation
    If hKey = 0 Or lpSubKey = "" Or lpString = "" Then GoTo ErrHandle
    
    'Open the given hkey + subkey
    If RegOpenKey(hKey, lpSubKey, hCurKey) = ERROR_SUCCESS Then
        'Create the given string + value
        If RegSetValueEx(hCurKey, lpString, 0, dwType, ByVal lpData, Len(lpData)) = ERROR_SUCCESS Then
            CREATE_REG_STRING = 1
        Else
            CREATE_REG_STRING = 0
        End If
    Else
        'Create the given hkey + subkey
        If RegCreateKey(hKey, lpSubKey, hCurKey) = ERROR_SUCCESS Then
            'Create the given string + value
            If RegSetValueEx(hCurKey, lpString, 0, dwType, ByVal lpData, Len(lpData)) = ERROR_SUCCESS Then
                CREATE_REG_STRING = 1
            Else
                CREATE_REG_STRING = 0
            End If
        Else
            CREATE_REG_STRING = 0
        End If
    End If
    RegCloseKey hCurKey
    
Exit Function
ErrHandle:
    CREATE_REG_STRING = 0
End Function

Public Function SET_STRING_VALUE(ByVal hKey As Long, ByVal lpSubKey As String, ByVal lpString As String, ByVal dwType As Long, ByVal lpData As String) As Long
On Error GoTo ErrHandle
    'Data validation
    If hKey = 0 Or lpSubKey = "" Or lpString = "" Then GoTo ErrHandle
    
    'Open the given hkey + subkey
    If RegOpenKey(hKey, lpSubKey, hCurKey) = ERROR_SUCCESS Then
        'Create the given string + value
        If RegSetValueEx(hCurKey, lpString, 0, dwType, ByVal lpData, Len(lpData)) = ERROR_SUCCESS Then
            SET_STRING_VALUE = 1
        Else
            SET_STRING_VALUE = 0
        End If
    Else
        SET_STRING_VALUE = 0
    End If
    RegCloseKey hCurKey
    
Exit Function
ErrHandle:
    SET_STRING_VALUE = 0
End Function