The image key returned by this property is contained in the ImageList property of the containing TreeView control.
The ImageKey is case-insensitive.
The ImageKey and ImageIndex properties are mutually exclusive; if one property is set, the other is ignored. If you set the ImageKey property, the ImageIndex property is automatically set to -1. Alternatively, if you set ImageIndex, ImageKey is automatically set to an empty string ("").
Windows 8.1, Windows Server 2012 R2, Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)