Validate field

if ($values["fieldname"] > 500)

{

$message = "The value of this field can not be greater than 500"

}
$values["fieldname"] is dependent on what event you're in. You could also use a simple vaiable name like $money.

I am looking for a way to prevent the user to add a value > 500 when validating with the save button (something like the required case)
Thanks for your help!
Pedro

I found the solution by using Regular expression on the field:
Add Page / Visual Editor/ Edit as / On Validate As / Regular Expression / Regexp = ^[0-5][0][0]$
May be helpful...
Thanks
Pedro