I\'m using this function to phone mask and works almost perfectly.
function mask(o, f)
{
v_obj = o;
v_fun = f;
setTimeout(\"execmask()\", 1)
};
function mask(o, f) {
setTimeout(function () {
var v = f(o.value);
if (v != o.value) {
o.value = v;
}
}, 1);
}
function mphone(v) {
var r = v.replace(/\D/g,"");
r = r.replace(/^0/,"");
if (r.length > 10) {
// 11+ digits. Format as 5+4.
r = r.replace(/^(\d\d)(\d{5})(\d{4}).*/,"(0XX$1) $2-$3");
}
else if (r.length > 5) {
// 6..10 digits. Format as 4+4
r = r.replace(/^(\d\d)(\d{4})(\d{0,4}).*/,"(0XX$1) $2-$3");
}
else if (r.length > 2) {
// 3..5 digits. Add (0XX..)
r = r.replace(/^(\d\d)(\d{0,5})/,"(0XX$1) $2");
}
else {
// 0..2 digits. Just add (0XX
r = r.replace(/^(\d*)/, "(0XX$1");
}
return r;
}
http://jsfiddle.net/BBeWN/
I love this function and I use it all the time. I've added 2 other masks if anyone needs them. I understand that they don't directly answer the question, but they are super useful.
//Social Security Number for USA
function mssn(v) {
var r = v.replace(/\D/g,"");
r = r.replace(/^0/,"");
if (r.length > 9) {
r = r.replace(/^(\d\d\d)(\d{2})(\d{0,4}).*/,"$1-$2-$3");
return r;
}
else if (r.length > 4) {
r = r.replace(/^(\d\d\d)(\d{2})(\d{0,4}).*/,"$1-$2-$3");
}
else if (r.length > 2) {
r = r.replace(/^(\d\d\d)(\d{0,3})/,"$1-$2");
}
else {
r = r.replace(/^(\d*)/, "$1");
}
return r;
}
//USA date
function mdate(v) {
var r = v.replace(/\D/g,"");
if (r.length > 4) {
r = r.replace(/^(\d\d)(\d{2})(\d{0,4}).*/,"$1/$2/$3");
}
else if (r.length > 2) {
r = r.replace(/^(\d\d)(\d{0,2})/,"$1/$2");
}
else if (r.length > 0){
if (r > 12) {
r = "";
}
}
return r;
}