how to check whether it is a character or a number using javascript..?

There is also a simple internal javascript function called isNaN(), meaning "is not a number".

It returns true (or -1) for non numeric values, and false (0) for numbers.

A decimal point inside a number is accepted as a number (for example "0.1"). isNaN is not locale dependant meaning that in countries using comma for decimal marker, we still get true from testing a value such as isNaN('0,1') )

use a regex:

http://www.javascriptkit.com/jsref/string.shtml

for example: myString.replace(/(\d+)\.+$/,"$1")