注册dll

unit Unit1;

interface

uses
  Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
  Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.StdCtrls;

type
  TForm1 = class(TForm)
    Button1: TButton;
    Button2: TButton;

    procedure Button1Click(Sender: TObject);
    procedure Button2Click(Sender: TObject);

    type

     TDllRegisterServer = function:HResult; stdcall;
  private

    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form1: TForm1;

implementation

{$R *.dfm}

function RegisterServer(const aDllFileName: string; aRegister: Boolean): Boolean;
type
  TRegProc = function: HResult;
  stdcall;
const
  cRegFuncNameArr: array [Boolean] of PChar =
    ('DllUnregisterServer', 'DllRegisterServer');
var
  vLibHandle: THandle;
  vRegProc: TRegProc;
begin
  Result := False;
  vLibHandle := LoadLibrary(PChar(aDllFileName));
  if vLibHandle = 0 then Exit;
    @vRegProc := GetProcAddress(vLibHandle, cRegFuncNameArr[aRegister]);
  if @vRegProc <> nil then
    Result := vRegProc = S_OK;
  FreeLibrary(vLibHandle);
end;

procedure TForm1.Button1Click(Sender: TObject);
begin
RegisterServer('EASendMailObj.dll',true);
end;

procedure TForm1.Button2Click(Sender: TObject);
begin
 RegisterServer('EASendMailObj.dll',FALSE);
end;

end.