How To Register ActiveX Control (OCX) From Delphi

Sometimes, when we make application that use OCX file, we must make sure that the ActiveX control is registered on our users machines.

for example when you import an ActiveX control into your project, you'll need to make sure that this ActiveX control is registered on your users machines. If the control is not registered there, an EOleSysError exception will be displayed to your user eyes.

we can use RegSvr32.exe manually (Windows.Start - Run) to register and unregister OLE controls such as dynamic link library (DLL) or ActiveX Controls (OCX) files that are self-registerable.

The regsvr32.exe command-line tool registers dll and ActiveX controls on a system. You can manually use the Regsvr32.exe (Windows.Start - Run) to register and unregister OLE controls such as dynamic link library (DLL) or ActiveX Controls (OCX) files that are self-registerable.
When you use Regsvr32.exe, it attempts to load the component and call its DLLSelfRegister function. If this attempt is successful, Regsvr32.exe displays a dialog indicating success.

the good news isbut we can import the activex control from delphi code runtime.

From Delphi Code we can do like this :

uses shellapi;
...
function ExecAndWait(const ExecuteFile, ParamString : string): boolean;
var
SEInfo: TShellExecuteInfo;
ExitCode: DWORD;
begin
FillChar(SEInfo, SizeOf(SEInfo), 0);
SEInfo.cbSize := SizeOf(TShellExecuteInfo);
with SEInfo do begin
 fMask := SEE_MASK_NOCLOSEPROCESS;
 Wnd := Application.Handle;
 lpFile := PChar(ExecuteFile);
 lpParameters := PChar(ParamString);
 nShow := SW_HIDE;
end;
if ShellExecuteEx(@SEInfo) then
begin
 repeat
   Application.ProcessMessages;
   GetExitCodeProcess(SEInfo.hProcess, ExitCode);
 until (ExitCode <> STILL_ACTIVE) or Application.Terminated;
 Result:=True;
end
else Result:=False;
end;

procedure RegisterOCX;
type
TRegFunc = function : HResult; stdcall;
var
ARegFunc : TRegFunc;
aHandle  : THandle;
ocxPath  : string;
begin
try
ocxPath := ExtractFilePath(Application.ExeName) + 'Flash.ocx';
aHandle := LoadLibrary(PChar(ocxPath));
if aHandle <> 0 then
begin
 ARegFunc := GetProcAddress(aHandle,'DllRegisterServer');
 if Assigned(ARegFunc) then
 begin
   ExecAndWait('regsvr32','/s ' + ocxPath);
 end;
 FreeLibrary(aHandle);
end;
except
ShowMessage(Format('Unable to register %s', [ocxPath]));
end;
end;