Ciao [trodat],
ti faccio un esempio
codice:
<script language="javascript">
function dataValida(txt){
var re = /^\d{1,2}\/\d{1,2}\/\d{4}$/
if(re.test(txt)){
var adata = txt.split('/');
var gg = parseInt(adata[0],10);
var mm = parseInt(adata[1],10);
var aaaa = parseInt(adata[2],10);
var xdata = new Date(aaaa,mm-1,gg)
if((xdata.getFullYear()==aaaa) && (xdata.getMonth()==mm-1) && (xdata.getDate()==gg))
return xdata
else return false
}else return false
}
function Controlla(ff){
if(ff.es.checked)
if(!dataValida(ff.data_int.value)){
alert('check selezionato! Inserire una data valida');
return false
}
return true
}
</script>
<form name="NomeForm" onsubmit="return Controlla(this)">
<input type="checkbox" name="es" value="checkbox">
<input type="text" name="data_int" value="">
<input type="submit" value="submit">
</form>