Cuadro de diálogo Buscar

Buenas,

Resulta que en el cuadro de dià¡logo Buscar (Edición -

Buscar), aparece una opción que se llama "Incluir
caracteres de uno y de dos bytes"; ¿para qué sirve?

Muchas gracias
.

Fuentes y caracteres de un byte y de dos bytes.

Cada carácter de una fuente utiliza un trazo o combinación
de trazos para producir el carácter.

Las fuentes basadas en la mayoría de los idiomas
occidentales tienen 256 caracteres posibles.

Cada carácter de esas fuentes tiene un tamaño de un byte.

Un caracter de un byte puede tener uno de entre 256
posibles valores.

Un byte tiene 8 bits, y cada bit es uno de dos valores
posibles (o es un "1" o es un "0") eso es 2 elevado a 8
(2x2x2x2x2x2x2x2) (2 multiplicado por 2, por 2...) o lo
que es lo mismo, 256.

Otros idiomas pueden necesitar más de 256 caracteres. Los
lenguajes asiáticos (japonés, chino, coreano, ...)
necesitan muchos más caracteres que los lenguajes
occidentales por lo que requieren dos bytes para cada
carácter.

Cada carácter en una fuente de dos bytes tiene uno de
entre 65.536 posibles valores (256 multiplicado por 256).


Mucho Mejor Información (English):
leeds.ac.uk/acom/teaching/mlc/handouts/lecture2_handout.pdf

Y de Robert Sprung:

"The problem goes back to the early days of computing,
when a single byte was chosen to be the "word" that the
computer spoke. One byte is composed of eight bits (zeroes
or ones) and could represent 256 possible combinations.
Thus was born the ASCII standard, which has remained with
us to this day.
ASCII contained all common English characters-the standard
was, after all, developed largely by U.S. powerhouses like
IBM. It included diacritical marks for the major European
languages (umlaut, acute and grave accents, tilde). If you
used a computer anywhere in the world, an "A" on one
machine would be an "A" on another ASCII-based machine-as
long as your language was English, Spanish, or French.
But standard ASCII was simply too limited to accommodate
non-Roman languages such as Russian or Czech, to say
nothing of ideographic languages like Chinese or Japanese.
Since there is no global standard for Greek, for example,
a simple Greek text file on a Macintosh will often be
unreadable on a PC without custom software-the antithesis
of an "open" system.
The answer to this linguistic Babel has been known to
computer scientists for years. Using two bytes instead of
one would suddenly open up enough space for most of the
world's languages. If one byte can store 256 characters,
two bytes can store 216 possible characters (16 zeroes or
ones in any combination), for a total of 65,536!
This is enough for all languages your company is currently
using in labeling-French, Finnish, Greek, or Japanese-as
well as any you might add. Unicode covers Arabic, Bengali,
Korean, Tibetan. . . you get the picture. It also includes
arrows, diacritical marks, math symbols, and dingbats.
If a two-byte standard like Unicode is so logical, why
wasn't it adopted decades ago? Limited computing power
made every byte precious, but the answer lies deeper. At
midcentury, the computing world was English-centric (some
felt that English would emerge as the universal language
of the computer-both for written communication and for
programming). Why invest heavily in a standard for Chinese
or Hindi when practically no one even owned a computer in
countries using those languages or when they might end up
using English anyway?
Today, the computing world is decidedly international and
multilingual. Given tremendous strides in computing power,
booming international trade, and the World Wide Web,
Unicode's day has dawned. The standard is supported by
such firms as IBM, Xerox, Microsoft, Sun, and Oracle. And
many products are already Unicode enabled: Microsoft
Windows NT and Windows 2000; Java, IBM OS/2, Oracle 8; and
Netscape Navigator."

Cordialmente

Enric