Search results
Results from the WOW.Com Content Network
In SGML, HTML and XML documents, the logical constructs known as character data and attribute values consist of sequences of characters, in which each character can manifest directly (representing itself), or can be represented by a series of characters called a character reference, of which there are two types: a numeric character reference and a character entity reference.
Incorrect HTML entity escaping may also open up security vulnerabilities for injection attacks such as cross-site scripting. If HTML attributes are left unquoted, certain characters, most importantly whitespace, such as space and tab, must be escaped using entities. Other languages related to HTML have their own methods of escaping characters.
In HTML 4, there is a standard set of 252 named character entities for characters - some common, some obscure - that are either not found in certain character encodings or are markup sensitive in some contexts (for example angle brackets and quotation marks). Although any Unicode character can be referenced by its numeric code point, some HTML ...
This page lists codes for keyboard characters, the computer code values for common characters, such as the Unicode or HTML entity codes (see below: Table of HTML values"). There are also key chord combinations, such as keying an en dash ('–') by holding ALT+0150 on the numeric keypad of MS Windows computers. The HTML codes can be used where a ...
As of version 4.0, HTML defines a set of 252 character entity references and a set of 1,114,050 numeric character references, both of which allow individual characters to be written via simple markup, rather than literally. A literal character and its markup counterpart are considered equivalent and are rendered identically.
There is another kind of character reference called a character entity reference, which allows a character to be referred to by a name instead of a number. (Naming a character creates a character entity.) HTML defines some character entities, but not many; all other characters can only be included by direct encoding or using NCRs.
HTML and XML provide ways to reference Unicode characters when the characters themselves either cannot or should not be used. A numeric character reference refers to a character by its Universal Character Set/Unicode code point, and a character entity reference refers to a character by a predefined name. A numeric character reference uses the ...
Although any character can be referenced using a numeric character reference, a character entity reference allows characters to be referenced by name instead of code point. For example, HTML 4 has 252 built-in character entities that do not need to be explicitly declared, while XML has five. XHTML has the same five as XML, but if its DTDs are ...