var isShift = false;
var seperator = "/";

function DateFormat(txt, keyCode) {

    if (keyCode == 16)

        isShift = true;

    //Validate that its Numeric

    if (((keyCode >= 48 && keyCode <= 57) || keyCode == 8 ||

         keyCode <= 37 || keyCode <= 39 ||

         (keyCode >= 96 && keyCode <= 105)) && isShift == false) {

        if ((txt.value.length == 2 || txt.value.length == 5) && keyCode != 8) {

            txt.value += seperator;
        }

        return true;
    }

    else {

        return false;
    }
}