Using the not indicator
On some occasions, an event needs to be handled when a parameter is not a specified value. When a
parameter should not be a certain value, use either the exclamation point (
!) or the tilde
(~) value modifier before the value of the parameter. For an event handler that is run only
if the condition is not accepted, the condition parameter is specified as follows:
<PARAMETER name="condition">!Accepted</PARAMETER>You need to be aware of how comma-separated values are treated before you use a not indicator in a list of
multiple values. Lists of states typically require every value to match. That is, commas are treated as a
logical AND and the not indicator applies to just one particular state. For all other comma-separated lists,
use a not indicator with only a single value because they look for any value to match. Using two not
indicators in a list results in filtering nothing. For example, if you specify !2,!5, every
value matches because 2 is not equal to 5 and 5 is not equal to 2. Instead, list all the allowed values.