Hide CreditCardNumber Field

Hi All,

I have Employee form that form have CreditCardNumber Field is there when ever enter creditcardnumber automatically its changes to  Like ***********1111

EX: CreditCardNumField: 1111 1111 1111 1111 then next **** **** **** 1111 i want to see last four digits only how to achive this senario by using javascript or jquery help me.

Regards,

Naresh