Category : Databases and related files
Archive   : MF-DB102.ZIP
Filename : MF.BAS

Option Explicit
'************* MF DLL calls ***************

' Use this file with any program you create in VB
' It contains all the declarations needed for accessing
' the MF database.

' *** ADMIN ***
Declare Function mfInit% Lib "mf.dll" (extensionDLLs As Any)
Declare Function mfDeInit% Lib "mf.dll" (ByVal task%)
Declare Function mfOpen% Lib "mf.dll" (ByVal FileName$, ByVal task%)
Declare Function mfClose% Lib "mf.dll" (ByVal task%, ByVal dbHndl%)
Declare Function mfCreateDB% Lib "mf.dll" (ByVal FileName$, ByVal RecSize%, ByVal NumIndexs%, rSizeArray As Any, typeArray As Any)

' *** GENERAL ***
Declare Function mfInfoDB% Lib "mf.dll" (RecSize%, NumIndexs%, NumRecs&, LiveRecs&, ByVal task%, ByVal dbHndl%)
Declare Function mfInfoIndex% Lib "mf.dll" (ByVal task%, ByVal dbHndl%, ByVal indexNumber%)
Declare Function mfIsDeleted% Lib "mf.dll" (ByVal RecordNum&, ByVal task%, ByVal dbHndl%)
Declare Function mfReIndex% Lib "mf.dll" (ByVal anHwnd%, ByVal task%, ByVal dbHndl%)
Declare Function mfLock% Lib "mf.dll" (ByVal RecordNum&, ByVal task%, ByVal dbHndl%)
Declare Function mfUnLock% Lib "mf.dll" (ByVal RecordNum&, ByVal task%, ByVal dbHndl%)




' *** DATA I/O ***
Declare Function mfRead% Lib "mf.dll" (ByVal RecordNum&, record As Any, ByVal task%, ByVal dbHndl%, ByVal opt%)
Declare Function mfWrite% Lib "mf.dll" (ByVal RecordNum&, record As Any, ByVal task%, ByVal dbHndl%, ByVal opt%)
Declare Function mfDelete% Lib "mf.dll" (ByVal RecordNum&, ByVal task%, ByVal dbHndl%)
Declare Function mfAppendData& Lib "mf.dll" (record As Any, ByVal task%, ByVal dbHndl%)

' *** Movement ***
Declare Function mfTop& Lib "mf.dll" (ByVal task%, ByVal dbHndl%, ByVal indexNumber%)
Declare Function mfBottom& Lib "mf.dll" (ByVal task%, ByVal dbHndl%, ByVal indexNumber%)
Declare Function mfSkip& Lib "mf.dll" (ByVal FromRecord&, ByVal HowFarToSkip&, ByVal task%, ByVal dbHndl%, ByVal indexNumber%)
' Since VB doesn't support passing 'void' pointers -- we have to trick it to do the job
' SeekS is for STRINGS
' SeekO is for anything else...
Declare Function mfSeekS& Lib "mf.dll" Alias "mfSeek" (ByVal skStr$, retcode%, ByVal task%, ByVal dbHndl%, ByVal xNum%)
Declare Function mfSeekO& Lib "mf.dll" Alias "mfSeek" (skStr As Any, retcode%, ByVal task%, ByVal dbHndl%, ByVal xNum%)


' Severe-Performance functions
Declare Function mfReadListS& Lib "mf.dll" Alias "mfReadList" (ByVal record As Long, ByVal skStr$, ByVal FuzzyLength%, hitList As Any, ByVal maxHits&, ByVal task%, ByVal dbHndl%, ByVal xNum%)
Declare Function mfReadListO& Lib "mf.dll" Alias "mfReadList" (ByVal record As Long, skStr As Any, ByVal FuzzyLength%, hitList As Any, ByVal maxHits&, ByVal task%, ByVal dbHndl%, ByVal xNum%)
Declare Function mfReadListNull& Lib "mf.dll" Alias "mfReadList" (ByVal record As Long, ByVal skStr As Long, ByVal FuzzyLength%, hitList As Any, ByVal maxHits&, ByVal task%, ByVal dbHndl%, ByVal xNum%)



' Constants:
' READ and WRITE options
Global Const MFRW_ALL = -1
Global Const MFRW_DATA = -2
Global Const MFRW_KEY = -3

' Seek Top/Bottom
' Return codes when there's no higher/lower key
' or no data at all...
Global Const MFSEEK_BOF = -1
Global Const MFSEEK_EOF = -2
Global Const MFSEEK_NODATA = -3

' parameter set in iCode for an mfSeek
Global Const MFSEEK_EXACT_MATCH = 1
Global Const MFSEEK_PARTIAL_MATCH = 2

' SP constants
Global Const MF_SP_COUNT = -1

' index type information
Global Const MFCOMP_CHAR = 1
Global Const MFCOMP_INT = 2
Global Const MFCOMP_LONG = 3
Global Const MFCOMP_CHARIC = 4 ' Case insensitive strings
Global Const MFCOMP_UDK = 100 ' Or greater...

' used for an array on index sizes on createDB
Type tIntArray
i As Integer
End Type

' Used for getting a hit-list in the severe-performance functions
Type tLongArray
l As Long
End Type

' Required on mfInit when using extensions to MF
Type tExtDLL
type As Integer
DLLName As String * 128
End Type

' Need 1 task handle per application instance
Global TaskHndl As Integer ' Task handle # for this instance

Sub mfBeginRun ()
ReDim extDLLs(0 To 1) As tExtDLL

extDLLs(0).type = MFCOMP_UDK ' tells mf to use this dll for UDK's
extDLLs(0).DLLName = "mfUDK.dll"
extDLLs(1).type = -1 ' tells MF there are NO more extensions to load


' Add this line as the first line in your application
' (or, at least before you use the dbms)
' The TaskHndl is your unique handle to the database
' If the hndl is -1, then 10 apps are already accessing the
' database -- close some!
TaskHndl = mfInit(extDLLs(0))
If TaskHndl < 0 Then
MsgBox "No database handles available -- please close some active windows"
End
End If
End Sub

' Call when you are completely done with the database
' for the entire program...
Sub mfEndRun ()
junk = mfDeInit(TaskHndl)
End Sub

' Pad a string with 'char'
Function Pad$ (num%, char$)
Dim n%, r$
For n = 1 To num
r = r + char
Next n
Pad = r
End Function