library demodll;

{ Important note about DLL memory management: ShareMem must be the
  first unit in your library's USES clause AND your project's (select
  Project-View Source) USES clause if your DLL exports any procedures or
  functions that pass strings as parameters or function results. This
  applies to all strings passed to and from your DLL--even those that
  are nested in records and classes. ShareMem is the interface unit to
  the BORLNDMM.DLL shared memory manager, which must be deployed along
  with your DLL. To avoid using BORLNDMM.DLL, pass string information
  using PChar or ShortString parameters. }

uses
   SysUtils,
   Classes,
   UDemo in 'UDemo.pas' {Demo};

{$R *.res}
procedure ShowdemoForm;stdcall;
begin
   Demo :=Tdemo.Create(nil);
   demo.Show;
end;

function ShowdemoFormModal:integer;stdcall;
begin
   demo :=Tdemo.Create(nil);
   Result := demo.ShowModal;
end;

Exports
   ShowDemoForm,
   ShowdemoFormModal;
begin
end.

unit UMain;

interface

uses
   Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
   Dialogs, StdCtrls, ExtCtrls;

type
TShowdemoFormModal= Function :integer;
.
.
.

var
hndDLLHandle:THandle;
ShowdemoFormModal:TShowdemoFormModal;

procedure TFMain.Button1Click(Sender: TObject);
begin
   try
      hndDLLHandle:=LoadLibrary('Demodll.dll');

      if hndDLLHandle <> 0 then begin
         @ShowdemoFormModal:=getProcAddress(hndDLLHandle,'ShowdemoFormModal');

         if addr(ShowdemoFormModal) <> nil then begin
            ShowdemoFormModal;
         end
         else
            showmessage ('function not exists ...');
         end
      else
         showMessage('Dll Not Found!');
      finally
         freelibrary(hndDLLHandle);
      end;
end;