Unicode

打开网址http://inamidst.com/stuff/unidata/

可以查看unicode以及对应的字符：

点击选择一个字符后，会转到http://www.fileformat.info这个网址，这个网站上会显示该字符的详细信息，包Unicode Data，Encodings，在html/c/c++/java/python 语言中的编码信息。

比如下面是美元符号的信息：

Unicode DataNameDOLLAR SIGNBlockBasic LatinCategorySymbol, Currency [Sc]Combine0BIDIEuropean Number Terminator [ET]MirrorNIndex entriesmilreis
DOLLAR SIGN
escudoCommentsmilreis, escudo
glyph may have one or two vertical bars
other currency symbol characters: U+20A0-U+20B8See Alsocurrency sign U+00A4
heavy dollar sign U+1F4B2VersionUnicode 1.1.0 (June, 1993)EncodingsHTML Entity (decimal)$HTML Entity (hex)$How to type in Microsoft WindowsAlt +0024
Alt 036
Alt 36UTF-8 (hex)0x24 (24)UTF-8 (binary)00100100UTF-16 (hex)0x0024 (0024)UTF-16 (decimal)36UTF-32 (hex)0x00000024 (0024)UTF-32 (decimal)36C/C++/Java source code"\u0024"Python source codeu"\u0024"More...Java Datastring.toUpperCase()$string.toLowerCase()$Character.UnicodeBlockBASIC_LATINCharacter.charCount()1Character.getDirectionality()DIRECTIONALITY_EUROPEAN_NUMBER_TERMINATOR [5]Character.getNumericValue()-1Character.getType()26Character.isDefined()YesCharacter.isDigit()NoCharacter.isIdentifierIgnorable()NoCharacter.isISOControl()NoCharacter.isJavaIdentifierPart()YesCharacter.isJavaIdentifierStart()YesCharacter.isLetter()NoCharacter.isLetterOrDigit()NoCharacter.isLowerCase()NoCharacter.isMirrored()NoCharacter.isSpaceChar()NoCharacter.isSupplementaryCodePoint()NoCharacter.isTitleCase()NoCharacter.isUnicodeIdentifierPart()NoCharacter.isUnicodeIdentifierStart()NoCharacter.isUpperCase()NoCharacter.isValidCodePoint()YesCharacter.isWhitespace()No

wiki 上code point的解释：

In character encoding terminology, a code point or code position is any of 

the numerical values that make up the code space (or code page).^[1] 

For example, ASCIIcomprises 128 code points in the range 0_hex to 7F_hex, 

Extended ASCII comprises 256 code points in the range 0_hex to FF_hex, and 

Unicode comprises 1,114,112 code points in the range 0_hex to 10FFFF_hex.

The Unicode code space is divided into seventeen planes (the basic multilingual 

plane, and 16 supplementary planes), each with 65,536 (= 2¹⁶) code points. 

Thus the total size of the Unicode code space is 17 × 65,536 = 1,114,112.

在Python中，可以通过unicode name的取得相应的字符，如可以通过名字'dollar sign',

来得到dollar符号：

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>>> dollar = u"\N{dollar sign}"
>>> print dollar
$

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