.net - Can't find System.Windows.Vector in C#

Question

I'm making a Windows Forms application in Visual Studio 2010 Ultimate, but can't get the built-in Vector to work.

Microsoft says that there is a System.Windows.Vector in the .NET Framework 4:

Maybe I'm making some large mistake, but Visual Studio complains about trying to use Vector in any way, and it doesn't come up in the IntelliSense autocomplete:

The line Vector v = new Vector(20, 30); gives

Compile error Error 1 The type or namespace name 'Vector' could not be found (are you missing a using directive or an assembly reference?)"

I tried including a using System.Windows at the top but that didn't solve the problem.

I went to References -> Add Reference to try to find something to add, but nothing was obvious.

The problem may be: Also listed with Vector in the System.Windows namespace, there are other classes like Rect or Application. I could use these as System.Drawing.Rectangle or System.Windows.Forms.Application, but none of these show up as part of some System.Windows namespace

I've tried different things for about 2 hours, and found this related post (but Vector is part of .NET 4, so their fix doesn't seem worthwhile?) and this possibly related post but I do have .NET Framework 4 installed.

Does anyone have an example of Vector? I know I could get a third party class, but I feel I'm missing something, and want to learn/have the solution posted for other people googling the same problem.

Answer 1

Add a reference to WindowsBase.
The Vector class is defined in the WindowsBase.dll assembly within the System.Windows namespace.