var
isZeroChamp = false;
function keyup (champ, nomChampSuiv, nomChampPrec) {
var code = -1;
if (window.event && window.event.keyCode) code = window.event.keyCode;
if
(code >= 0 && code != 8 && code < 32) return;

var n = champ.value.length;
if(
nomChampSuiv && (
(champ.maxlength && champ.maxlength <=
n)
|| (champ.maxLength && champ.maxLength <= n)
|| (champ.size && champ.size <= n)
)) {
var c = champ.form.elements[nomChampSuiv];
c.focus();
c.select();
}
if
(nomChampPrec && n <= 0 && isZeroChamp ) {
var c = champ.form.elements[nomChampPrec];
c.focus();
if (code == 8)
c.value = c.value.substring(0,
c.value.length-1);

c.value += "";
}
isZeroChamp = (n==0);
}