Not all ActiveX controls have been recompiled for the64 bit versions of Microsoft Windows. Various areas of the 3ds Max User Interface rely on ActiveX controls like TreeView and ListView. To provide an alternative implementation of these and other controls,3ds Max 9 and higher provide access to DotNet Classes, Objects and Methods and provides a dotNetControl User Interface Control to use in MAXScript Rollouts.
MAXScript / DotNet Value Conversions
Creating A Simple DotNet MonthCalendar And Changing Its Colors
Creating A Simple Web Browser Using DotNet
Converting Scripts From Using ActiveX Controls to DotNet Controls
Converting ActiveX ListView Control to DotNet ListView Control
Converting ActiveX TreeView Control to DotNet TreeView Control
[3dsMax Path]\stdplugs\stdscripts\NET_ListViewWrapper.ms
This script contains useful functions for creating and managing ListView DotNet controls.
[3dsMax Path]\stdplugs\stdscripts\NET_TreeViewWrapper.ms
This script contains useful functions for creating and managing TreeView DotNet controls.
[3dsMax Path]\ui\macroscripts\Macro_BakeTextures.mcr
The Render To Texture dialog has been updated to use DotNet ListView controls instead of ActiveX controls.
[3dsMax Path]\ui\macroscripts\Macro_NamedSelSets.mcr
The Named Selection Sets editor dialog has been updated to use a DotNet TreeView control instead of an ActiveX control. It is a good example of using Drag And Drop in DotNet TreeView controls.
Microsoft Developers Network Library - System.Windows.Forms documentation:
http://msdn2.microsoft.com/en-us/library/system.windows.forms.aspx