Use the SelectAll method to select all visible items in the
tree.
The SelectAll method has effect only if the SingleSel
property is False, if the control supports multiple items selection. Use the UnselectAll
method to unselect all items in the list. Use the SelectItem
property to select or unselect a specified item. Use the SelectedItem
property to retrieve a value that indicates whether the item is selected or
unselected. Use the SelectCount property
to retrieve the number of selected items. The SelectPos
property selects/unselects items by position. The Selection
property selects/unselects items by index.