VBAPI.INC

[Tyrone W. Lee]

Nifty.. I will save that information.. Though, I have just converted
my code to use an array buffer that holds multiple linked lists
within it by index.

I use the PRESERVE command to ReDIM a larger array as new elements
are added to the link list..

But I'll save those API commands for later.



------------------
Explorations v3.0 RPG Development System
http://www.explore-rpg.com

[Florent Heyworth]

If you want to allocate strings dynamically use the
SysAllocStringByteLen() function to allocate and
SysFreeString() to free the string. As in the following
example:

#COMPILE EXE
 
DECLARE FUNCTION SysAllocStringByteLen LIB "OLEAUT32.DLL" ALIAS "SysAllocStringByteLen" ( _
                                                                    szOleChar AS ASCIIZ, _
                                                                    BYVAL lLen AS LONG _
                                                                    ) AS DWORD
                                                                             
DECLARE SUB SysFreeString LIB "OLEAUT32.DLL" ALIAS "SysFreeString" ( BYVAL dwBstr AS DWORD )
 
SUB TestString( szString AS ASCIIZ )
     
    STDOUT szString
     
END SUB
 
FUNCTION PBMAIN() AS LONG
    LOCAL pszString AS ASCIIZ PTR
     
    pszString = SysAllocStringByteLen( "HELLO THERE", 11 )
     
    CALL TestString( @pszString )
     
    CALL SysFreeString( pszString )
     
    WAITKEY$
     
END FUNCTION

------------------

[Tyrone W. Lee]

I want to allocate memory blocks to form a link list of data. (Database
records.)

I have several databases on disk that I load into and manipulate
in memory as if they were on disk. Basically a memory random access
file. You can read, write, append, and instert records in memory
as if u were writing to disk.

I can't use arrays because there are several of these databases in
operation at the same time. (not all the same size) So arrays
would waste memory space.

I will check out the Windows memory Allocate command but PB should
really include the original GetStrAlloc, RlsStrAlloc from v2.0
Its a MUCH NEEDED command for real pointer Link Lists..



------------------
Explorations v3.0 RPG Development System
http://www.explore-rpg.com

[Bern Ertl]

Tyrone,

Is the intention is to create temporary strings, why not
let PB do it for you? Just use a regular string and initialize
it to the size you need?

If you need ASCIIZ, just add CHR$(0) to the end...

Ie.:

LOCAL TempStringSpace$
LOCAL BytePtr AS BYTE PTR

TempStringSpace$ = SPACE$( NumBytesNeeded&)
BytePtr = STRPTR( TempStringSpace$)
'Process string with pointer...
....
'Release old string space, create new space
TempStringSpace$ = SPACE$( NumBytesNeeded&)
BytePtr = STRPTR( TempStringSpace$)
'Process string with pointer...

------------------
Bernard Ertl

[Michael Mattias]

Under PB/DLL 6, you do dynamic memory allocation using the Win32API calls GlobalAlloc/HeapAlloc, GlobalLock and GlobalUnlock and GlobalFree.

(All the Globalxxx have a companion Heapxxx function).

MCM

[Tyrone W. Lee]

Ok.. I found out how to pass strings in PB6.0.. But what about
dynamic memory allocation. GetStrAlloc and RlsStrAlloc? I have
a v2.0 .DLL that uses these function heavily with pointers and
I need a v6.0 equivalent.

Please help me on this one? If there isn't a command can I use
PB v2.0 and link it with v6.0?

------------------
Explorations v3.0 RPG Development System
http://www.explore-rpg.com

[Lance Edmonds]

Passing strings back and forth with VB is covered in the help file under "Appendix B", and in the FAQ forum...


------------------
Lance
PowerBASIC Support
mailto:[email protected][email protected]</A>

[Wayne Diamond]

Something like this?

 
[b]PB: The DLL[/b]
FUNCTION MAKEUCASE(inString AS ASCIIZ PTR) EXPORT AS STRING
ON ERROR RESUME NEXT
FUNCTION = UCASE$(@inString)
END FUNCTION
 
[b]VB: Calling the DLL[/b]
Private Declare Function MAKEUCASE Lib "myucase.dll" (ByVal inString As String) As String
Private Sub Form_Load()
Dim TestString As String
TestString = "test"
MsgBox "MAKEUCASE returned " & MAKEUCASE(ByVal TestString)

Best of luck,
Wayne


------------------

[Tyrone W. Lee]

Ok.. Now that I can link 32bit PB DLL's with VB5.. I have another issue.
I am trying to return string variables from PB to VB5. I tried
to import the VBAP.INC but I get an error. Is there a VBAPI32.INC
available yet? Or how can I return strings (ASCIIZ) from PB to VB5?

Also, I would like to know the 32bit PowerBasic equivalent to GetStrAlloc
and RlsStrAlloc..


------------------
Explorations v3.0 RPG Development System http://www.explore-rpg.com

[This message has been edited by Tyrone W. Lee (edited April 18, 2001).]