This sample demonstrates the Header Template functionality in QueryBuilder control using DropDownList and Button controls. In this sample, user can change the Condition using DropDownList control and adding rules, groups and deleting groups by using Button control.
This sample illustrates how to integrate HeaderTemplate in the QueryBuilder. This is used for creating custom user interface for the header with custom controls and update the rule collection by using the control events. More information about Query Builder can be found in this documentation section.