How to improve TextBox performance and scroll down on refresh?

Question

WPF

In general, I decided to rewrite the old project under WPF with MVVM and ran into such a problem
... enough text.
I would like to make sure that the entire text is not redrawn, but only a new one is added. Well, after the update, scroll down. At the same time, it is imperative to preserve the MVVM approach.

Answer 1

Event TextChanged -> (sender as TextBox).ScrollToEnd();
The text will still be replaced.
Only the visible part is drawn. But, if there is a ScrollBar, the control needs to know the height of the entire text, and when the text is inserted, the height of the entire text is recalculated. Especially if TextWrapping is installed.