HTML Unicode (UTF-8) 参考

The Unicode Consortium

The Unicode Consortium develops the Unicode Standard. Their goal is to replace the existing character sets with its standard Unicode Transformation Format (UTF).

The Unicode Standard has become a success and is implemented in HTML, XML, Java, JavaScript, E-mail, ASP, PHP, etc. The Unicode standard is also supported in many operating systems and all modern browsers.

The Unicode Consortium cooperates with the leading standards development organizations, like ISO, W3C, and ECMA.

The Unicode Character Sets

Unicode can be implemented by different character sets. The most commonly used encodings are UTF-8 and UTF-16:

Character-set Description
UTF-8 A character in UTF8 can be from 1 to 4 bytes long. UTF-8 can represent any character in the Unicode standard. UTF-8 is backwards compatible with ASCII. UTF-8 is the preferred encoding for e-mail and web pages
UTF-16 16-bit Unicode Transformation Format is a variable-length character encoding for Unicode, capable of encoding the entire Unicode repertoire. UTF-16 is used in major operating systems and environments, like Microsoft Windows, Java and .NET.

Tip: The first 128 characters of Unicode (which correspond one-to-one with ASCII) are encoded using a single octet with the same binary value as ASCII, making valid ASCII text valid UTF-8-encoded Unicode as well.

HTML 4 supports UTF-8. HTML 5 supports both UTF-8 and UTF-16!

The HTML5 Standard: Unicode UTF-8

Because the character sets in ISO-8859 were limited in size, and not compatible in multilingual environments, the Unicode Consortium developed the Unicode Standard.

The Unicode Standard covers (almost) all the characters, punctuations, and symbols in the world.

Unicode enables processing, storage, and transport of text independent of platform and language.

The default character encoding in HTML-5 is UTF-8.

If an HTML5 web page uses a different character set than UTF-8, it should be specified in the <meta> tag like:


<meta charset="ISO-8859-1">

The Difference Between Unicode and UTF-8

Unicode is a character set. UTF-8 is encoding.

Unicode is a list of characters with unique decimal numbers (code points). A = 65, B = 66, C = 67, ....

This list of decimal numbers represent the string "hello": 104 101 108 108 111

Encoding is how these numbers are translated into binary numbers to be stored in a computer:

UTF-8 encoding will store "hello" like this (binary): 01101000 01100101 01101100 01101100  01101111

Encoding translates numbers into binary. Character sets translates characters to numbers.

HTML5 UTF-8 Character Codes

Below is a list of some of the UTF-8 character codes supported by HTML5:

Character codes Decimal Hexadecimal
C0 Controls and Basic Latin 0-127 0000-007F
C1 Controls and Latin-1 Supplement 128-255 0080-00FF
Latin Extended-A 256-383 0100-017F
Latin Extended-B 384-591 0180-024F
Spacing Modifiers 688-767 02B0-02FF
变音标记 768-879 0300-036F
希腊和科普特人 880-1023 0370-03FF
西里尔字母 1024-1279 0400-04FF
西里尔字母补充 1280-1327 0500-052F
一般标点 8192-8303 2000-206F
货币符号 8352-8399 20A0-20CF
字母符号 8448-8527 2100-214F
箭头 8592-8703 2190-21FF
Mathematical Operators 8704-8959 2200-22FF
箱型图 9472-9599 2500-257F
块元素 9600-9631 2580-259F
几何形状 9632-9727 25A0-25FF
Miscellaneous Symbols 9728-9983 2600-26FF
丁巴特 9984-10175 2700-27BF

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