Adding HTML entities using CSS content

Question

How do you use the CSS content property to add HTML entities?

Using something like this just prints   to the screen instead of the non-breaking space:

.breadcrumbs a:before {
    content: ' ';
}

Answer 1

You have to use the escaped unicode :

Like

.breadcrumbs a:before {
    content: '\0000a0';
}

Answer 2

CSS is not HTML.   is a named character reference in HTML; equivalent to the decimal numeric character reference  . 160 is the decimal code point of the NO-BREAK SPACE character in Unicode (or UCS-2; see the HTML 4.01 Specification). The hexadecimal representation of that code point is U+00A0 (160 = 10 × 16¹ + 0 × 16⁰). You will find that in the Unicode Code Charts and Character Database.

In CSS you need to use a Unicode escape sequence for such characters, which is based on the hexadecimal value of the code point of a character. So you need to write

.breadcrumbs a:before {
 content: '\a0';
}

This works as long as the escape sequence comes last in a string value. If characters follow, there are two ways to avoid misinterpretation:

a) (mentioned by others) Use exactly six hexadecimal digits for the escape sequence:

.breadcrumbs a:before {
 content: '\0000a0foo';
}

b) Add one white-space (e. g., space) character after the escape sequence:

.breadcrumbs a:before {
 content: '\a0 foo';
}

(Since f is a hexadecimal digit, \a0f would otherwise mean GURMUKHI LETTER EE here, or ਏ if you have a suitable font.)

The delimiting white-space will be ignored, and this will be displayed  foo, where the displayed space here would be a NO-BREAK SPACE character.

The white-space approach ('\a0 foo') has the following advantages over the six-digit approach ('\0000a0foo'):

• it is easier to type, because leading zeroes are not necessary, and digits do not need to be counted;
• it is easier to read, because there is white-space between escape sequence and following text, and digits do not need to be counted;
• it requires less space, because leading zeroes are not necessary;
• it is upwards-compatible, because Unicode supporting code points beyond U+10FFFF in the future would require a modification of the CSS Specification.

Thus, to display a space after an escaped character, use two spaces in the stylesheet –

.breadcrumbs a:before {
 content: '\a0 foo';
}

– or make it explicit:

.breadcrumbs a:before {
 content: '\a0\20 foo';
}

Answer 3

PointedEars mentions that the correct stand in for   in all css situations would be
'\a0 ' implying that the space is a terminator to the hex string and is absorbed by the escaped sequence. He further pointed out this authoritative description which sounds like a good solution to the problem I described and fixed below.

What you need to do is use the escaped unicode. Despite what you've been told \00a0 is not a perfect stand-in for   within CSS; so try:

content:'>\a0 '; /* or */
content:'>\0000a0'; /* because you'll find: */
content:'No\a0 Break'; /* and */
content:'No\0000a0Break'; /* becomes No Break as opposed to below */

Specifically using \0000a0 as  . If you try, as suggested by mathieu and millikin:

content:'No\00a0Break' /* becomes No਋reak */

It takes the B into the hex escaped characters. The same occurs with 0-9a-fA-F.