I have a ScrollViewer and in that I am showing the Vertical Scrollbar, Now on changing resolution of the system I want to get the width of the scrollbar. I went through One StackOverflow Post there they mention to check for SystemParameters.ScrollWidth Property but again I din find any help from their. Can anybody please help me to fix my issue. Any answer will be appreciated.
I think SystemParameters.VerticalScrollBarWidth is what you are looking for.
I am not sure if this is the correct answer. Every WPF control can be restyled so even the scrollbar. So SystemParameters.VerticalScrollBarWidth works only if it is used as default scrollbar. The correct solution would be to find the vertical scrollbar in the visual tree and measure it's ActualWidth. It is the most precise measurement.
来源：https://stackoverflow.com/questions/5701760/how-to-find-vertical-scrollbar-width-of-a-scrollviewer-in-c-sharp