Re: Accessing DLL from Ruby

Hi Bob
Thanks for the prompt help.
I will try this. Now I can convince my colleagues to use Ruby!

V V Kanetkar
  ----- Original Message ----- 
  From: Bob Calco 
  To: [e-mail] 
  Sent: Wednesday, March 03, 2004 9:49 AM
  Subject: Re: Accessing DLL from Ruby


  V.V.:

   

  This is because VB dll's are ActiveX dlls; they adhere to the COM binary specification, and do not export their functions via the C calling convention (cdecl). You would do well to register the VB dll (regsvr32.exe <dllname> at the command line), find its program ID (for instance, MS Word's is "Word.Application") - something you can do either by searching the registry, or by selecting it from the available list inside of MS Office VBA development environment (Go to Tools->References, a list of all registered COM servers will magically appear; one of them should be your prjCalc.dll if you successfully registered it).

   

  The point is, once you get the VB DLL's Program ID, you can do this instead in Ruby:

   

  require 'win32ole'

   

  MyDLL = WIN32OLE.new("<program_id>")

  res = MyDLL.calc(<number>)

  puts res.to_s

   

  -          Bob Calco

   


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

  From: V KANETKAR [mailto:[e-mail]] 
  Sent: Tuesday, March 02, 2004 10:56 PM
  To: [e-mail]
  Subject: Accessing DLL from Ruby

   

  I have a problem:

  I am trying to call a function from a Visual Basic DLL. I wrote following code but Ruby gave error.

  I need to resolve this and need expert Ruby?windows help.

   


  #Ruby Program to load dll(Just loading)
  require 'Win32API'
  dllcalc=Win32API.new("E:\\download\\sudha\\prjCalc.dll","calc",["I"],'I')

   


  # Error 

   

  >ruby dmapi.rb
  dmapi.rb:2:in `initialize': GetProcAddress: calc or calcA (RuntimeError)
   from dmapi.rb:2:in `new'
   from dmapi.rb:2
  >Exit code: 1

   

   

   

  # The Visual Basic Code for the dll. Contains only one function calc. Returns integer, i/p is one integer
  # Works OK in VB. The dll was registered in Registry: same error.

   

  Public Function calc(intVal1 As Integer) As Integer
      calc = -intVal1
  End Function

   

   

   


  # A similar example given in "Pragmatic Programmer"  works finr!

   

  # Please Help

   

  V V Kanetkar