Editing Windows Forms (section)

== Alternative implementation ==
[[Mono (software)|Mono]] is a project led by [[Xamarin]] (formerly by [[Ximian]], then [[Novell]]) to create an [[Ecma International|Ecma]] standard compliant [[.NET Framework]] compatible set of tools.

In 2011, [[Mono (software)|Mono]]'s support for System.Windows.Forms as of [[.NET Framework version history#.NET Framework 2.0|.NET 2.0]] was announced as complete;<ref>{{cite web
| url=http://www.mono-project.com/WinForms
| title= WinForms
| publisher=mono-project.com
| quote=''Support for Windows Forms 2.0 is complete. At this point, we are largely just fixing bugs and polishing our code. ''
| access-date=2011-07-30}}</ref>
System.Windows.Forms 2.0 works natively on Mac OS X.<ref>{{cite web
| url=http://www.mono-project.com/FAQ:_Winforms
| title= WinForms
| publisher=mono-project.com
| quote=''Does Winforms run on OSX? Yes, as of Mono 1.9, Winforms has a native OSX driver that it uses by default''
| access-date=2011-07-30}}</ref>
However, System.Windows.Forms has not been actively developed on Mono.<ref>{{cite web
 |url=http://tirania.org/blog/archive/2011/Mar-07.html
 | title=GDC 2011
 | last=de Icaza
 | first=Miguel
 | author-link=Miguel de Icaza
 |date=2011-03-07
 |access-date=2011-07-30
 |quote=''For tools that are mostly OpenGL/DirectX based, use Windows.Forms, keeping in mind that some bug fixing or work around on their part might be needed as our Windows.Forms is not actively developed.''}}</ref>
Full compatibility with .NET was not possible, because Microsoft's System.Windows Forms is mainly a wrapper around the [[Windows API]], and some of the methods allow direct access to Win32 [[Callback (computer programming)|callbacks]], which are not available in platforms other than Windows.<ref name="monofaq-winform"/>
A more significant problem is that, since version 5.2,<ref>{{cite web
 |url=https://www.mono-project.com/docs/about-mono/supported-platforms/macos/
 | title=Introduction to Mono on macOS
 | publisher=mono-project.com
 | access-date=2019-11-12
}}</ref>
Mono has been upgraded so that its default is to assume a 64 bit platform.
However, System.Windows.Forms on Mono for the Macintosh OS X platform has been built using a 32 bit subsystem, [[Carbon (API)|Carbon]].<ref>{{cite web
 |url=https://www.infoq.com/news/2018/02/mono-forms-carbon64/
 | title=Windows.Forms Comes to 64-bit Mac OS X
 | last=Martin
 | first=Jess
 | access-date=2019-11-12
}}</ref>
As of this date{{when|date=January 2021}}, a 64-bit version of System.Windows.Forms for use on Mac OS X remains unavailable and only .NET applications built for the 32 bit platform can be expected to execute.