// Create via DLL Wizard:
library TestDLL;

uses
  SysUtils,
  Classes,
  Dialogs;

{$ R * .res}

// Building process
procedure Test;
begin 
  ShowMessage ('TestDLL.Test');
end ;

// output
exports
  Test;

begin
end .


// Call in other projects, if not in a project group, need to be in the same directory, under System32, or specify the path;
// Declaration can be in the implementation area or interface area. The function names here must be consistent, even case.

// Call test:
procedure Test;external 'TestDLL.dll';

procedure TForm1.Button1Click (Sender: TObject);
begin
  Test;
end ;