<script type = "text/javascript">
function randomString() {
    var chars = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXTZ";
    var string_length = 8;
    var randomstring = '';
    for (var i=0; i<string_length; i++) {
        var rnum = Math.floor(Math.random() * chars.length);
        randomstring += chars.substring(rnum,rnum+1);
    }
    return randomstring;
}
function setCookieOnLoad(){
var cookName = "VOUCHER";
var cookVal = randomString();
var date = new Date();
date.setTime(date.getTime()+(30*24*60*60*1000));
var expireDate = date.toGMTString();
var myCookie = cookName + "=" + cookVal + ";expires=" + expireDate;
document.cookie = myCookie;
}
</script>