how can I integrate C program in VB express?

how can I integrate C program in VB express?

• gtjr92

  Oh, VS6. Use DumpBin /exports on your DLL to find out the exact spelling of the export name in the DLL. You can use DependencyWalker too. You can use a .def file to force the name exactly the way you want it.
  
  
  

• PK2000

  I thought the easy way is APP...

  So if you can explain how can I integrate Application it be great. And I be glad to hear about the other two ways if you can explain them to me with details.. Best Regards, Yaniv

  
  

• jitendra badkas

  Hmm, I actually tried it before I posted. This was my C++ source code:
  

• Leaf.

  C++ mangles the symbol. Use extern "C" to stop the mangling:
  
  extern "C" double __declspec(dllexport) b5(int x) {
  return x;
  }
  
  
  
  

• Mikaelm

  Here's what I did to test. Created a C Win32 DLL, removed all the superfluous ***, including the precompiled headers:

  Created a file called test.cpp

  #include <windows.h>
  float __stdcall DoMultiply( float x, float y)
  {
  return x * y;
  }

  Added a .DEF file, also:

  LIBRARY "test"
  EXPORTS
  DoMultiply @1

  Compiled it into a DLL (removed the precompiled headers that the 'wizard' put in), then created a VB Windows program:

  Public Class Form1
  
  Private Declare Auto Function DoMultiply Lib "test.dll" (ByVal x As Single, ByVal y As Single) As Single
  
  Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
  Dim result As Single = DoMultiply(45, 7.3)
  MessageBox.Show(result.ToString)
  End Sub
  End Class

  Ensured the DLL was in the same folder as the VB EXE. Now the C program is ready for fine tuning, but that basically works.

  
  
  

• Ephi

  thank you... it's working...

  I'm really appreciate all of you for your help...

  Best Regards,

  Yaniv

  
  

• Ion101

  Create a .DEF file in the C project, with something like:

  LIBRARY MyFileName

  EXPORTS
      MyFunction      @1
      MyOtherFunction @2

  And change the declaration to __stdcall instead of __declspec(dllexport).

  See if that works.

  
  
  

• mahima

  I tried extern "C" I get the same error...

  any more ideas

  
  

• djshades2004

  I wrote dumpbin /exports b1.dll and I get this information:

  Dump of file b1.dll

  file type: DLL

  summary

  4000 .data

  1000 .idata

  2000 .rdata

  2000 .reloc

  28000 .text

  and in the b1.def file I saw this :

  # microsoft Developer studio............,included by b1.mak

  ./stdafx.cpp : /

  "..\..\vc98\include\basetsd.h"\

  ".\stdafx.h"\

  So I don't understand how this information help me

  
  

• sascue

  I tried to do a sample program that using DLL

  in c++ =>B1.DLL:

  double __declspec(dllexport) b5(int x) {
  x=5;
  return x;
  }

  in vb .net:

  Public Class Form1

  Public Declare Ansi Function b5 Lib "b1.dll" (ByVal x As Integer) As Double

  Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load

  Dim y As Double

  Dim x As Integer

  x = 9

  y = b5(x)

  MsgBox(y)

  End Sub

  End Class

  I get an error = > in the line y= b5(x) => Unable to find an entry point named 'b5' in DLL 'b1.dll'.

  any ideas what I'm doing wrong

  Regards,

  Yaniv

  
  

• Matt354245

  still the same error...

  I copy paste the code in C++ and VB and I get the same error maybe I'm doing something wrong in VS6 C++...

  this is how I open a new DLL file:

  File=> New

  projects=> win32 dynamic-link library

  files=> c/c++ Header File

  I copy paste your code

  and click the Bulid(F7) button

  and copy the DLL file to the debug VB folder.

  what I'm doing wrong...

  thank you for you help... I'm really appreciate it

  Yaniv

  
  

• robertje

  Do yo have the raw C code or is it a dll or app If it is a dll then you either need to declare a reference or import the dll
  
  

• Benj78

  No, an app is infinitely harder than a DLL, if possible at all. Create a DLL with the C/C++ compiler, use __declspec(dllexport) on the functions that you want to use in your VB program. Then in your VB program, declare the functions with the Declare statement. The trivial example is:
  
  In 'C':
  double __declspec(dllexport) MyCFunction(int arg) {
  // blabla
  }
  
  In VB.NET:
  Public Declare Ansi Function MyCFunction Lib "myclibrary.dll" (ByVal arg As Integer) As Double
  
  
  
  
  
• how can I integrate C program in VB express?