This combo box lets the user pick a color from a list of colors using a subclass of ListComboBox. The user can also enter arbitrary CSS color names or values. This demonstrates how to use a text box class (here, ColorSwatchTextBox) and a list item class (LabeledColorSwatch) to provide custom rendering and validation for both input and choices. The base ListComboBox class provides AutoComplete functionality, matching against the provided list of color choices.

This control was discussed in a user interface blog post.