Serves as the base for classes, performing operations on rows.
The VGridControlBase descendants enables you to traverse through rows using the rows iterator technology, this means you don’t have to write recursive code. The Rows Iterator is an object that can be accessed via the grid’s VGridControlBase.RowsIterator property. Methods of this class require a RowOperation descendant to be sent to them as a parameter, this parameter specifies the operation performed on each visited row.
The RowOperation class is abstract. You must derive a custom class from it that will represent the desired operation (calculating the number of rows, expanding or collapsing each visited row etc).
The logic must be implemented in the RowOperation.Execute method, this method is called for each visited row. The currently visited row is sent to it as the parameter.
Override the RowOperation.Init method if you need to perform actions prior to the recursion starting. Alternatively, the RowOperation.Release method allows you to perform operations after all rows have been visited (calculating the average values within the processed rows, for instance).
To perform a specific operation you must call the VGridRowsIterator.DoOperation or VGridRowsIterator.DoLocalOperation method of the Rows Iterator and pass the operation object to it. The first scans through all rows within the control. The second is used to visit rows of a sub-tree whose parent is specified by the parameter.