Sets the level of grouping.
[Visual Basic] Sub SetLevel( _ ByVal p_nValue As Integer _ ) [C#] void SetLevel( int p_nValue ); [C++] void SetLevel( int p_nValue ); [JScript] function SetLevel( int p_nValue );
The level value is zero-based (no group).
IFilterItem Interface | Okapi.Library.Filter Namespace | GetLevel | SetGroupID