Celsius symbol in RichTextBox
Do you mean Celsius symbol as in 37°C? If so you can simply put that character where it should be, I guess:
richTextBox.Text = string.Format("{0}°C", degrees);If you are looking for character codes (or just want to find character to copy/paste them), you can use the Character Map application in Windows (in Start -> Programs -> Accessories -> System Tools).
Do you mean °C? You get ° from the keyboard as ALT + 0176 on the numeric keypad.
If you are wary of embedding a non-ASCII character in your source code, you could use the following instead:
richTextBox.Text = string.Format("{0}\u00B0C", degrees);(B0 is the hexadecimal for 176.)