Different filters behave differently if you pass it input data that the filter cannot process correctly.
Some filters (such as the
ToInt filter) will process only scalar data. If you pass an array to such filter,
it will return the array as is.
Some filters can work with data in certain format only (e.g., with dates only). If filtering
of input data is impossible (for example, when you pass the filter some wrong data that it is unable
to process), the
filter() method may throw a
This behavior can be seen in
It is recommended to read filter's documentation carefully to know what to expect of the filter you plan to use in your form.