library FirstDLLProject;
uses
SysUtils,Classes;
function Summ(X,Y:Integer) :Integer; StdCall;
begin
Result:=X+Y;
end;
exports Summ;
{$R *.res}
begin
end.

*************************************************
unit Unit1;
interface
uses
Windows, Messages, SysUtils, Variants, Classes,
Graphics, Controls, Forms,Dialogs, StdCtrls;
type
TForm1 = class(TForm)
Button1: TButton;
procedure Button1Click(Sender: TObject);
private
{ Private declarations }
public
{ Public declarations }
end;

var
Form1: TForm1;
function Summ(X,Y:Integer):Integer; stdcall;
implementation
function Summ(X,Y:Integer):Integer;
external 'FirstDLLProject.dll' name 'Summ';
{$R *.dfm}

procedure TForm1.Button1Click(Sender: TObject);
var
h:integer;
begin
h:=Summ(10,34);
Application.MessageBox(PChar(IntToStr(h)), 'Результат = ');
end;

end.

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