c# - How do I compute the non-client window size in WPF?

Question

WPF has the SystemParameters class that exposes a great number of system metrics. On my computer I have noticed that a normal window has a title that is 30 pixels high and a border that is 8 pixels wide. This is on Windows 7 with the Aero theme enabled:

However, SystemParameters return the following values:

SystemParameters.BorderWidth = 5
SystemParameters.CaptionHeight = 21

Here I have disabled the Aero theme:

Now, SystemParameters return the following values:

SystemParameters.BorderWidth = 1
SystemParameters.CaptionHeight = 18

How do I compute the actual observed values by using SystemParameters?

Answer 1

For a resizable window you need to use a different set of parameters to compute the size:

var titleHeight = SystemParameters.WindowCaptionHeight
  + SystemParameters.ResizeFrameHorizontalBorderHeight;
var verticalBorderWidth = SystemParameters.ResizeFrameVerticalBorderWidth;

These sizes will change when you modify the theme.