How to use XMLHttpRequest in web service.js?

Hi, I’m testing one of the web service sample app on SmartTV (Web Service | Tizen Docs).
The service start/stop correctly, and it also works in background after web app exited. But I can’t use XMLHttpRequest in service.js, it throws exception “ReferenceError: XMLHttpRequest is not defined”. Can anyone tell me how to get around the issue?

Thanks in advance.
Bentao

It’s sorted.
I think It’d be good for new Tizen developer to know that Tizen web app uses webview runtime and web service uses Node JS.
Thanks.