...Call Procedures within a DLL?

//  Call DLL Program  (Normal Application Project)
//  This example calls a Quick Report within a DLL.
//  Author: Michael Casse.
//  18-12-2001.

unit uMain;

interface

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

type
  TForm1 = class(TForm)
    btnClose: TBitBtn;
    btnReport: TBitBtn;
    procedure btnReportClick(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form1: TForm1;

implementation

{$R *.DFM}

procedure TForm1.btnReportClick(Sender: TObject);
var
  LibHandle: THandle;
  fDisplaySampleReport: procedure;
  begin
    LibHandle := LoadLibrary('Report.dll');
    if LibHandle = 0 then
      raise Exception.Create('Unable to Load DLL...')
    else
    begin
      try @fDisplaySampleReport := GetProcAddress(LibHandle, 'DisplaySampleReport');
        if @fDisplaySampleReport <> nil then
          fDisplaySampleReport; // Invoke the Procedure within the DLL
      except
        on E: Exception do
          ShowMessage('Exception error: ' + E.Message);
      end;
    end;
    FreeLibrary(LibHandle); // Free Memory Allocated for the DLL
  end;

  end.

  ////////////////////////////////////////////////
  // DLL Project

library Report;

uses  SysUtils, Classes,
      uReport in 'uReport.pas' {Form1};

procedure DisplaySampleReport;
begin
  Form1 := TForm1.Create(nil);
  try
    Form1.QuickRep1.Preview;
  finally
    Form1.Free;
  end;
end;

exports  DisplaySampleReport;

end.

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