unit MainRrm;

interface
uses
    SysUtils, WinTypes, WinProcs, Messages, Classes, Graphics, Controls,
    Forms, Dialogs, StdCtrls, Mask;
type
    TMainForm = class(TForm)
        lblTotal: TLabel;
        lblQlbl: TLabel;
        lblDlbl: TLabel;
        lblNlbl: TLabel;
        lblPlbl: TLabel;
        lblQuarters: TLabel;
        lblDimes: TLabel;
        lblNickels: TLabel;
        lblPennies: TLabel;
        btnMakeChange: TButton;
        meTotalPennies: TMaskEdit;
        procedure btnMakeChangeClick(sender: TObject);
    end;

var MainForm: TMainForm;

implementation
uses PenniesInt;
{R *.DFM}

procedure TMainForm.btnMakeChangeClick(Sender: TObject);
var
    CoinsRec: TCoinsRec;
    TotPennies: word;
begin
    {call the DLL function to determine the minimum coins required
    for the amount of pennies specified}
    TotPennies:= PenniesToCoins(StrToInt(meTotalPennies.Text), @CoinsRec);
    with CoinsRec do
    begin
        {Now display the coin information}
        lblQuarters.Caption:= IntToStr(Quarters);
        lblDimes.Caption:= IntToStr(Dimes);
        lblNickels.Caption:= IntToStr(Nickels);
        lblPennies.Caption:= IntToStr(Pennies);
    end;
end;

end.

implementation

function PenniesToCoins(TotPennies: word; ChangeRec: PChangeRec): Word; stdcall; external 'PENNIESLIB.DLL';

unit MainFrm;

interface
uses
    SysUtils, WinTypes, WinProcs, Messages, Classes, Graphics, Controls,
    Forms, Dialogs, StdCtrls;

type
    TShowCalendar = function(AHandle: THandle; ACaption: String): TDateTime; Stdcall;

    EDLLLoadError = class(Exception);

    TMainForm = class(TForm)
        lblDate: TLabel;
        btnGetCalendar: TButton;
        procedure btnGetCalendarClick(Sender: TOnject);
    end;

var
    MainForm: TMainForm;

implementation
{$R *.DFM}

procedure TMainForm.btnGetCalendarClick(Sender: TObject);
var
    LibHandle: THandle;    //!!!!!
    ShowCalendar: TShowCalendar;    //!!!!!!
begin
    LibHandle:= LoadLibrary('CALENDARLIB.DLL');    //!!!!!!
    try
        if LibHandle = 0 then
            raise EDLLLoadError.Create('Unable to load DLL');

        @ShowCalendar:= GetProcAddress(LibHandle, 'ShowCalendar');

        if not(@ShowCalendar = nil) then
            lblData.Caption:= DateToStr(ShowCalendar(Application.Handle, Caption))
        else
            RaiseLastWin32Error;
    finally
        FreeLibrary(LibHandle);
    end;
end;

end.

function LoadLibrary(lpLibFileName: PChar): HMODULE; stdcall;

function FreeLibrary(hLibModule: HMODULE): BOOl; stdcall;

function GetProcAddress(hModule: HMODULE; lpProcName: LPCSTR): FARPROC; stdcall;