ControlContext :: orderColumn - Order column
The property returns the column number for the column by which a table, tree or list is ordered. When the collection control is not ordered by column (i.e. when it is unordered or ordered by database index), the property contains -1.
When the control is not a collection control that supports sort orders, the property trows an exception.
Return value: Column number ( int32 )
The column number is the relative position of a column in a table starting with column 0. When using complex columns consisting of several sub-columns, each sub-column counts as one column, i.e. columns are numbered regardless on the structure defined for the table line.