How to determine how many characters are left before line break in RichTextBox?

Question

C++ / C#

I need to perform a certain action when 4 characters are left to enter before the line is moved to a new line. I need to somehow find out how many characters are left from the right edge. Can you tell me how to set the right condition?

Answer 1

You can install some monospaced font, such as Courier New.
Calculate the maximum number of characters that fit into a string.
Ready!