1. you can use the validation expression to check for dates:
<br />
var Year="^[0-9]{4}$";<br />
as for the range i think you should use a range validater or custom validater to check for that.
in case you want the range like value like 2011-2012 then regex will be:
<br />
var Year="^[0-9-]{9}$";<br />