Question

DLL and PChar

Asked by: DelphiCool

Hi

I made a delphi dll
wich as a function like this :

 function abc( chaine : Pchar ) : PChar; stdcall;

With a delphi exe, no problem

But when I try to call this function with VB, there is a big problem.
How can I do, I think it's a problem with string and PChar.

PS I don't want to add BORLNDMM.DLL with mine.

Thanks

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Asked On
2002-02-18 at 23:24:45ID20268434
Topic

Delphi Programming

Participating Experts
3
Points
10
Comments
12

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Answers

 

by: MadshiPosted on 2002-02-18 at 23:44:51ID: 6809915

Why is this a 0 point question?

Anyway, the Delphi part looks okay, you don't need borlndmm.dll, when using pchar only. I guess you're doing something wrong on the VB side. All win32 APIs are built like that (pchar + stdcall), and VB can call them, too.

Regards, Madshi.

 

by: DelphiCoolPosted on 2002-02-18 at 23:59:56ID: 6809939

sorry for the 0 question :(

Yes in delphi it's ok, no problem
the problem is when I call my dll with a VB exe.
perhaps I 'll have to go to the VB part of this site

 

by: MadshiPosted on 2002-02-19 at 00:08:27ID: 6809950

Probably.

 

by: geobulPosted on 2002-02-19 at 01:03:03ID: 6810034

Hi,
You have to declare that func in VB this way:
Declare Function abc Lib "YourDLL" Alias "abc" (ByVal chaine As String) As String

Alias part is optional.

Regards, Geo

 

by: MrGhostPosted on 2002-02-19 at 05:27:45ID: 6810479

if you want your dll to be used with other application than delphi you shold use stdcall derective!!!

 

by: DelphiCoolPosted on 2002-02-19 at 06:42:50ID: 6810693

Thanks all
but it's a problem with VB in fact

 
My Function delphi is like this
function abc(first:pchar; second:pchar; third:pchar):integer; stdcall;

and I use it in vb like this

Private Declare Function abc Lib "abc.dll" (ByVal first As String, second As String, third As String) As Integer

 

---

Private Sub Command2_Click()
 Dim i As Integer
 
 i = b("AAA", "BBB", "CCC")

The first param is passed ok, but the param 2 and 3 are not passd well ???

 

by: geobulPosted on 2002-02-19 at 06:46:25ID: 6810705

Private Declare Function abc Lib "abc.dll" (ByVal first As String, ByVal second As String, ByVal third As String)
As Integer

Regards, Geo


 

by: DelphiCoolPosted on 2002-02-19 at 09:37:39ID: 6811106

Thanks geobul

I must clean my glasses ;-)

 

by: geobulPosted on 2002-02-19 at 10:13:05ID: 6811209

C grade based on 10 point question !!! What does it mean? Or must I clean my glasses too?

 

by: DelphiCoolPosted on 2002-02-19 at 22:10:05ID: 6812546

I am new here,
I don't know how this forum work.

I don't know how this question cost.

And what happens when I finnaly have 0 points ??

 

by: geobulPosted on 2002-02-20 at 00:39:08ID: 6812708

Hi DelphiCool,
Every day you receive 5 'question points' in your account. When you are accepting someone's answer, your account is debited with the amount of points you've specified (10 in this case). Depending on the grade, the expert receives 'expert points' in his/her account which are the question points multiplied by the grade (A = x4, B = x3, C = x2). When you receive a fast and complete answer to your question then the usual grade is expected to be A. If you choose another grade you are expected to explain what's wrong with the proposed solution.

I see now that it's your first accepted answer here and therefore everything is OK.

Have a nice day.

Regards, Geo

 

by: DelphiCoolPosted on 2002-02-20 at 03:36:26ID: 6812932

Thanks you more Geo.


DelphiCool

20120131-EE-VQP-002

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