Calling a function by hand

From: William Egge (remove_pro_remove_at_eggcentric.com)
Date: 12/08/04

  • Next message: Avatar Zondertau: "Re: Calling a function by hand" 
    Date: Wed, 8 Dec 2004 11:39:13 -0500

    Hello,

    I wanted to get some advice before starting a little project.

    I need to call a function at runtime but the number of arguments and their
    types, and the pointer to the function are not known until runtime.

    So, I need to call a function and pass the parameters "by hand" rather than the
    compiler doing it at compile time.

    I was going to create a procedure that accepts the function pointer and a
    variant open array, like the function Format('', []) does. Then I was going to
    call the function and pass the parameters.

    I know there are different calling conventions, stdcall, cdecl, etc... I assume
    that I will be able to call the function correctly if I know its calling
    convention and its parameters. The variant array will tell me what the parameter
    types are.

    The end resulting procedure I imagine is
    procedure CallFunction(AFunction: Pointer; Args: array of const);

    I want this to be able to call functions in C, C++, and Delphi. I may also want
    to call an object method in Delphi or C++.

    The possibility of getting return results, and var params might be necessary.

    What advice can you give me?

    William Egge
    http://www.eggcentric.com

  • Next message: Avatar Zondertau: "Re: Calling a function by hand"

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