Thread: Hai Everybody !VC dll in VB ?

  1. #1
    Registered User
    Join Date
    May 2002
    Posts
    21

    Unhappy Hai Everybody !VC dll in VB ?

    How to use a regular dll create using MFC Dll wizard in a vb application.

    I 've created a small dll by name sum(int,int) which returns an integer .

    I want to use this function in VB application.

    I will be glad if any body can help,

  2. #2
    Registered User
    Join Date
    May 2003
    Posts
    6
    Well, this is the way I did it:

    1. Make sure you use WINAPI as the calling convention for the functions you want to export (i.e. make available from VB), like this:
    Code:
    double WINAPI myFunc(double myVar)
    2. Add a def file to your project - it's just a text file like this:
    Code:
    LIBRARY myDLL
    EXPORTS
        myFunc
    Make sure there's an entry for each function you want to export.
    3. In VBA (probably the same in VB) put something like this in the declarations area:
    Code:
    Declare Function myFunc Lib "myDLL" (ByVal myVar As Double) As Double
    Make sure your DLL is in your system directory.

    I think that on 32-bit versions of Windows ints are 2 bytes in VB but 4 bytes in C, so you'll have to use short in your C code instead of int. Is there a 'cleaner' way of doing this? I don't know, I'm new to this.

    Hope that helps.

    N.

  3. #3
    id id
    Guest
    Use the long type in VB.

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