A Treeview Control/Component by Binarymission Technologies Ltd

The following are the rich features the control offers:

Support for "Tree-view" of data: The control directly supports displaying a tree-view drop-down of data!
All you need to do is to prepare a treeview object (or any object based on .NET TreeView control) with appropriate data and simply set it as the value of one of the control's property. That's it! Run your application and you will see a tree-view of your data.

Different levels of data presentation: The control supports two levels of data presentation.
By setting a simple property, you can specify whether to display in the combobox text portion, just the text relating to the selected node in the drop-down tree-view or to include the text of all the child nodes as well.

Highly configurable properties: The control's properties are highly configurable and easy to set. For example, you could set a custom "window close" image for the drop-down treeview window.

Ability to fully support "Control painting" with custom colors (with Alpha-blending support): Using the control's simple properties, you can now set custom colors of your choice, for drawing the ComboBox and other aspects like, item hovering background color, etc., along with full support for "Alpha blending" of colors.
The control also provides the capability for you to set an alpha-blending color factor of your choice, while setting the control's various color properties.

Mouse hovering effects - When the input focus is not on the control, whenever the mouse focus moves over and out of the control, the control's borders are drawn and cleared respectively, giving a "Visual Studio .NET style" control hovering effects.
Optionally, you can also set the control's ShowBorderAlways property to true, if you want the control's border to be displayed irrespective of whether the control has input focus or otherwise.