Welcome to OGeek Q&A Community for programmer and developer-Open, Learning and Share
Welcome To Ask or Share your Answers For Others

Categories

0 votes
846 views
in Technique[技术] by (71.8m points)

visual c++ - Confusion on Unicode and Multibyte Articles

By referring Joel's Article

Some people are under the misconception that Unicode is simply a 16-bit code where each character takes 16 bits and therefore there are 65,536 possible characters. This is not, actually, correct.

After reading the whole article, my point is that, if someone told you, his text is in unicode, you will have no idea how much memory space taken up by every of his character. He have to tell you, "My unicode text is encoded in UTF-8", then only you will have idea how much memory space is taken up by every of his character.

Unicode = not necessary 2 byte for each character


However, when comes to Code Project's Article and Microsoft's Help, this confused me :

Microsoft :

Unicode is a 16-bit character encoding, providing enough encodings for all languages. All ASCII characters are included in Unicode as "widened" characters.


Code Project :

The Unicode character set is a "wide character" (2 bytes per character) set that contains every character available in every language, including all technical symbols and special publishing characters. Multibyte character set (MBCS) uses either 1 or 2 bytes per character

Unicode = 2 byte for each character ?

Is 65536 possible characters able to represent all language in this world?

Why the concept seems different among web developer community and desktop developer community?

See Question&Answers more detail:os

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
Welcome To Ask or Share your Answers For Others

1 Reply

0 votes
by (71.8m points)

Once upon a time,

  • Unicode had only as many characters as fit in 16 bits, and
  • UTF-8 did not exist or was not the de facto encoding to use.

These factors led to UTF-16 (or rather, what is now called UCS-2) to be considered synonymous with “Unicode”, because it was after all the encoding which supported all of Unicode.

Practically, you will see “Unicode” being used where “UTF-16” or “UCS-2” is meant. This is a historical confusion and should be ignored and not propagated. Unicode is a set of characters; UTF-8, UTF-16, and UCS-2 are different encodings.

(The difference between UTF-16 and UCS-2 is that UCS-2 is a true 16-bits-per-“character” encoding, and therefore encodes only the “BMP” (Basic Multilingual Plane) portion of Unicode, whereas UTF-16 uses “surrogate pairs” (for a total of 32 bits) to encode above-BMP characters.)


与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
OGeek|极客中国-欢迎来到极客的世界,一个免费开放的程序员编程交流平台!开放,进步,分享!让技术改变生活,让极客改变未来! Welcome to OGeek Q&A Community for programmer and developer-Open, Learning and Share
Click Here to Ask a Question

...