MultiSelection
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Shows how to implement multi-range selection.

Depending on the setting of the SelectioMode property, the C1FlexGrid 
allows the selection of a single arbitrary range, groups of adjacent 
rows or columns, or arbitrary rows (ListBox mode).

This sample inherits from the grid and adds a new selection mode
similar to the one in Excel, where the user can select any number
of ranges. The ranges may be of any size and they don't have to be
adjacent.


