You know, if this is your final project, then I would have thought that by now you would have good google-fu skills.
But it would appear that your interpretation of "I searched a lot" differs from mine: I copied your question subject into Chrome's address bar and pressed ENTER...Oh, look! 282,000 results...
Google "measure the distance of an object using kinect"[
^]
And look! Yes, it is possible! Like this description:
http://mathnathan.com/2011/02/depthvsdistance/[
^]
Now, ok, it doesn't give you the code, but hey! It's your project after all, so perhaps you should put some work into it...