is there any code that will prevents other looking at your source?

There was another topic. I believe the answer was no, unless you decrypt or was it incrypt your codes.
ex: have you seen trish's skins?
(trish is [2]nekked)

http://www.vortex-webdesign.com/help/hidesource.htm

NO THERE ISN'T!!!... javascript can be disabled, encryption broken, source code shown no matter what

nope, but you can try doing somethings to annoy them i guess. For example: right click-log out, right click-earthquake effect, etc..There is more in xanga script.