求救高手！javascript格式3.3333333333变为3.3

//number"0,000.00"
function funNumOut(ctrl){
var s = ctrl.value;
if(/[^0-9\.]/.test(s)) {
ctrl.value="0.00";
return;
}
s=s.replace(/^(\d*)$/,"$1.");
s=(s+"00").replace(/(\d*\.\d\d)\d*/,"$1");
s=s.replace(".",",");
var re=/(\d)(\d{3},)/;
while(re.test(s))
s=s.replace(re,"$1,$2");
s=s.replace(/,(\d\d)$/,".$1");
ctrl.value = s.replace(/^\./,"0.");
}
//number back "0000.00"
function funNumIn(ctrl) {
var tf = true;
while(tf){
if (ctrl.value.indexOf(',') != -1) {
ctrl.value = ctrl.value.replace(",","");
} else {
tf = false;
}
}
ctrl.select();