I\'m trying to create a WPF window that will encompass the entire Desktop working area. In WinForms I\'d do this by getting the Union of all the bounds in System.Windows.F
Try SystemParameters.VirtualScreen* (Top, Left, Height, and Width) properties. http://msdn.microsoft.com/en-us/library/system.windows.systemparameters.virtualscreenheight(v=VS.100).aspx
Don't use winforms api because it doesn't take into account the fact that WPF's measurement units are not pixels. I came across this issue just recently because I'm losing my vision and have my monitor set to a higher dpi. The codebase I was working on used the Winforms Settings and the UI was larger than my screen.
If you're going to use the winforms api. Look at this blog post on calculating the DPI factor.