well , i had to validate some complex data validation and instead of copying and paste of code from any example i learned RegExp today from following of the references .
hope it will help u too .
http://www.javascriptkit.com/jsref/regexp.shtml
http://javascriptkit.com/javatutors/redev2.shtml
http://www.breakingpar.com/bkp/home.nsf/0/87256B280015193F87256C87006CC664
Good Resources , they really helped a lot .