What is the WPF control that VS2010 uses for the code editor?

What is the WPF control tha开发者_高级运维t VS2010 uses for the code editor? Some time in the past, I tried to use the 1st WPF version but it performed very bad. Seams like the performance in the .NET 4 is far better.

My question is actually related with the fact that I'm very unhappy with the editors available for Windows and want to try made one by myself :) Any help will be very welcome.

Thanks

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VS2010 uses something Microsoft wrote for their own, internal use. It is not a redistributable control.

The best code editing control for WPF I've found (to date) is Actipro's SyntaxEditor.