I am encountering a scenario where I need to enforce a rule that a
submitted value is NOT equal to something else. Before I write it, I wonder
if anyone else has done this already.
Specifically, it's kind of an unusual situation where the user can insert
what I call a "location" into a db table, and this model supports one level
of nesting -- that is, a location can either be in another location, or it
can be a top-level location, that's it. These locations have an attribute
"type," and the rule I want to enforce is: a location of a given type
cannot have as parent a location of the same type. Example: a hotel room is
in a hotel. A hotel cannot be in another hotel.
The form has a select menus for choosing a parent location, and for choosing
the type of the location. I am thinking of writing a custom validator for
the "select type" element, and throwing the parent location's type_id at its
constructor. Then isValid($value) will simply compare $value to
$this->parent_type_id.
Do you think this makes sense?
class My_Validate_NotEqual
{
function __construct($valueThatShouldBeDifferent) {
$this->valueThatShouldBeDifferent = $valueThatShouldBeDifferent;
}
function isValid($value) {
// stuff omitted for brevity, but basically...
return $value != $this->valueThatShouldBeDifferent;
}
}
Thanks.
--
Demand health care for everyone:
http://mobilizeforhealthcare.org/
--
David Mintz
http://davidmintz.org/
