The t-filter (or text filter) is the anti-hero of the filter family. Standing in the shadows while the hierarchy and data filters get covered in all the glory, it is not often required to generate dynamic reports. But it is really helpful in adding utility and usability to your reporting suite.

Within a subset, a text filter allows you to select all elements that match a certain string criteria. You can use it to generate a list of rows or columns, but where it is really powerful is in filtering out elements for a combo box. When you are dealing with a large subset (tens or hundreds of thousands of elements), it is sometimes difficult to give the users anything to navigate effectively through a combo box on the web, in order to find the element they are after.

Using a text filter, the users can type into a cell the values that they would like to search for in the combo box filters down the elements to that list. It does not just return a straight list; it maintains the hierarchy structure and relationships in the combo box of all elements that satisfy the criteria.

The kicker here is the capability to use the default search wildcards (eg *, ?) or use perl expressions. Perl expressions open opened up for me a big world of new type of filters that I previously unaware of. For example you can search for multiple criteria, exclude criteria, etc.

For example, I want to search for all elements that contain either ‘North’ or ‘East’:

This example is located here. Another example can be found on the web security template.

On the report, you can see i have a toggle for users to switch per expressions on or off as they require.  Although powerful, perl expressions can sometime confuse users, so it is best to have an option to turn it off or on.