function RegActiveX(FileName:string):HRESULT;
var
hMod:Integer;
RegProc:function:HRESULT; //HRESULT = Longint
begin
hMod:=LoadLibrary(FileName);
if hMod=0 then
raise Exception.Create('Unable to load library"'+FileName+'". GetLastError = '+IntToStr(GetLastError));
RegProc:=GetProcAddress(hMod,'DllRegisterServer');
if RegProc=nil then
raise Exception.Create('Unable to load "DllRegisterServer" function from "'+FileName+'". GetLastError = '+IntToStr(GetLastError));
Result:=RegProc;
end;

procedure RegisterTypeLibrary(FileName:string);
var
Name: WideString;
HelpPath: WideString;
TypeLib: ITypeLib;
begin
if LoadTypeLib(PWideChar(WideString(FileName)), TypeLib)=S_OK then
begin
Name := FileName;
HelpPath := ExtractFilePath(ModuleName);
RegisterTypeLib(TypeLib, PWideChar(Name), PWideChar(HelpPath));
end;
end;

function GetModuleFileName: string;
var Buffer: array[0..261] of Char;
begin
SetString(Result, Buffer, Windows.GetModuleFileName(HInstance,
Buffer, SizeOf(Buffer)));
end;