Interview Questions

What does \ABCD (and \ABCDE) mean?

CSS Interview Questions and Questions

(Continued from previous question...)

17. What does \ABCD (and \ABCDE) mean?

CSS allows Unicode characters to be entered by number. For example, if a CLASS value in some Russian document contains Cyrillic letters EL PE (Unicode numbers 041B and 041F) and you want to write a style rule for that class, you can put that letter into the style sheet by writing:

.\041B\041F {font-style: italic;}
This works on all keyboards, so you don't need a Cyrillic keyboard to write CLASS names in Russian or another language that uses that script.

The digits and letters after the backslash (\) are a hexadecimal number. Hexadecimal numbers are made from ordinary digits and the letters A to F (or a to f). Unicode numbers consist of four such digits.

If the number starts with a 0, you may omit it. The above could also be written as:

.\41B\41F {font-style: italic;}
But be careful if the next letter after the three digits is also a digit or a letter a to f! This is OK: .\41B-\41F, since the dash (-) cannot be mistaken for a hexadecimal digit, but .\41B9\41F is only two letters, not three.

Four digits is the maximum, however, so if you write:
.\041B9\041F {font-style: italic;}

(Continued on next question...)

Other Interview Questions