Navigation: ABC Library Reference > QueryClass > QueryClass Methods >====== QueryClass Functional Organization–Expected Use  ====== |    |
As an aid to understanding the QueryClass, it is useful to organize its various methods into two large categories according to their expected use–the primary interface and the virtual methods. This organization reflects what we believe is typical use of the QueryClass methods.
Non-Virtual Methods
The Non-Virtual Methods, which you are likely to call fairly routinely from your program, can be further divided into three categories:
Housekeeping (one-time) Use:
| Init | initialize the QueryClass object | |
| AddItem | add a field to query | |
| Kill (v) | shut down the QueryClass object |
Mainstream Use:
| Ask (v) | a virtual to accept query criteria | |
| GetFilter | return filter expression |
Occasional Use:
| Reset | reset the QueryClass object | |
| GetLimit | get searchvalues | |
| SetLimit | set search values |
(v)These methods are also Virtual.
Virtual Methods
Typically you will not call these methods directly–other ABC Library methods call them. However, we anticipate you will often want to override these methods, and because they are virtual, they are very easy to override. These methods do provide reasonable default behavior in case you do not want to override them.
| Ask | a virtual to accept query criteria | |
| Kill | shut down the QueryClass object |