Mehul
By "validation" I'm going to make an assumption that you are referring to LiveCycle Designer form validation.
LiveCycle Designer allows the use of either Javascript of FormCalc whereas the script object you can use within Workbench utilizes BeanShell - a small scripting language based on Java.
As far as making use of an external js file for use in validation within Designer, you can reference "trusted" functions. These functions can be stored in files within the app.path directory and can be referenced from within your form. However, this then means that any user who is to use the form you've created will have to have a copy of the trusted code file on their local system or the form will error when it tries to call the code.
Your best bet is to just copy any of the javascript code from your external file into Designer and let it run from within the form.
Josh Boyle
jboyle@cardinalsolutions.com
Cardinal Solutions Group
