HTML entity
An HTML entity is an entity (i.e. a clearly delimitable character string with a special meaning) that is used in HTML (i.e. the text-based markup language in which, for example, websites can be formulated). Are often used where numeric entities and named entities to characters to describe (if they specifically in the selected for the website coding or used to compile input method are not available.) Also, certain control characters can be so visibly displayed in the text.
Numeric entities
A numeric entity denotes a character by its Unicode code point. Two formats are defined for this:
-
&#nnn;
- nnn represents the code point as a decimal number (without leading zeros). -
&#xhhhh;
- hhhh represents the code point as a hexadecimal number , that is, as the Unicode code point is usually specified (without the introductory "U +"). Leading zeros can be specified and are common for less than four-digit values so that the value is the same as the four-digit Unicode code point specification.
Regardless of the code (" charset ") in which the HTML document is available, only the code point in Unicode applies. This means that numeric entities in the range €
to Ÿ
or hexadecimal €
to are Ÿ
incorrect if they are used to represent characters that have code points in this range in the Windows-1252 code. These include a. the characters € and ‰, the letters Œ, œ, Š, š, Ÿ, Ž and ž as well as various quotation marks and dashes . Characters with Unicode code points from U+0080
to U+009F
do not normally appear in texts.
Named Entities
A named entity has the format - aaa represents a name consisting of uppercase and lowercase letters from the basic Latin alphabet and digits, which uniquely identifies the character to be designated. Upper and lower case letters are to be used exactly and can have different meanings. The names are determined by the W3C ( World Wide Web Consortium ).
&aaa;
Examples
character | Unicode | designation |
Decimal code |
Numeric entity | Named Entity |
||
---|---|---|---|---|---|---|---|
position | Surname | decimal | hexadec. | ||||
· | U + 00B7 | middle dot | Half-high point | 0183 | & # 183; | & # x00B7; | · middot; |
ſ | U + 017F | latin small letter long s | long s | 0383 | & # 383; | & # x017F; | (no) |
‰ | U + 2030 | per mille sign | Alcohol symbol | 8240 | & # 8240; | & # x2030; | & permil; |
? | U + 1F5B7 | fax icon | Fax icon | 128439 | & # 128439; | & # x1F5B7; | (no) |
The fact that the alcohol symbol 0137
can also be written with the decimal code under Windows cannot be used for HTML entities.
Individual evidence
- ↑ W3C ( World Wide Web Consortium ): Character entity references in HTML 4 - List of named entities that are available in HTML 4 (and thus, for example, for the creation of Wikipedia articles)
- ↑ W3C ( World Wide Web Consortium ): Character entity reference chart - List of named character entities available in HTML 4 and HTML5