So it's not a CIDR.
It'll be much easier.
Create a regex like below for field "a"
^([01]?\d\d?|2[0-4]\d|25[0-5])(?:\.[01]?\d\d?|\.2[0-4]\d|\.25[0-5]){3}(\/([01]?\d\d?|2[0-4]\d|25[0-5]))$
Client Script
function onChange(control, oldValue, newValue, isLoading) {
if (isLoading || newValue == '') {
return;
}
try {
var mask = g_form.getValue('a').split('/');
var end = mask[1];
var maskOctet = mask[0].split('.');
var endOctet = newValue.split('.');
for (var i=0; i<3; i++) {
if (maskOctet[i] != endOctet[i]) {
g_form.showFieldMsg('b', 'invalid ip address.', 'error');
return;
}
}
if (endOctet[3] < 1 || endOctet[3] > end) {
g_form.showFieldMsg('b', 'invalid ip address.', 'error');
}
} catch (e) {
alert(e.message);
}
}
