How do I change background color of a text range in WPF TextBox?

Question

I want to change background color for some portions of text (from begin and end absolute char positions) of a TextBox control.

(either from user selection start and end OR from preloaded start and end absolute character positions)

Is this possible?

NOTE I do not want to use RichTextBox or any Flow Document.

Can't with TextBox but in TextBlock e.g Hi Color Me No Color ? — Shubham Sahu, Nov 19 '18 at 16:16
I used this answer. I will delete my answer. https://stackoverflow.com/questions/751741/wpf-textblock-highlight-certain-parts-based-on-search-condition — paparazzo, Nov 19 '18 at 16:19

score 0 · Answer 1 · answered Nov 19 '18 at 16:25

Unless text selection is sufficient, you can't do it directly with a textbox. I recommend you think carefully about whether selecting a text range is sufficient. You can do that based on character from and to and you could override the system brush making it whatever colour you like.

If that isn't sufficient then.

You'd need some other control under the textbox which made it look like it's the background of the textbox changing. One way to do this would be to use an itemscontrol you template into textblocks and colour their backgrounds.

You put that under your textbox so it's background shows through. Probably best to set the text the same colour as your background as well so no small offsets cause problems.

Alternatively, you could use a lineargradientbrush and calculate where the characters are. This would be quite tricky though.

How do I change background color of a text range in WPF TextBox?

1 Answers1