This interface defines methods that can be used to launch a custom System.Drawing.Design.UITypeEditor object for assigning URLs (BuildUrl( )) or colors (BuildColor( )).

public interface IWebFormsBuilderUIService {
// Public Instance Methods
   public string BuildColor(System.Windows.Forms.Control owner, string initialColor);
   public string BuildUrl(System.Windows.Forms.Control owner, string initialUrl, string baseUrl, 
        string caption, string filter, UrlBuilderOptions options);
}