Hello all,
perhaps I solved it:
This is the syntax that seems to work:
((isset($_POST["myselect"]) && $_POST["myselect"] == "8" && $_POST["field1"] < "100" && $_POST["field2"] < "120" )?"-1":"0")
Please note I used server validation as NUMBER (minimum: 0).
Do you see something wrong here?
Is there something better for it?
TIA
tony