Thread: Change RichTextBox Color

I want to change specific text color in a RichTextBox. I want to insert something with a specific color. The solutions I find by googling require, if I understand correctly, that you read again all the text and then paint it accordingly. Can't you just insert something, color it and stay colored?

The methods I use is Select() to select a text and SelectionColor to change it. It seems simple but it doesn't really work for me.

Like, will this color blue str inserted to output rich text box?

Code:

output.Text += str;
output.Select(output.Text.Length - 1 - str.Length, str.Length);
output.SelectionColor = Color.Blue;