(, ENTITY) XML , : XML-; DTD- ; , DTD- ; , DTD .
(internal entities)
XML- DTD( XML), XML-. , (&) . :
&surname;
DTD - filename.dtd !DOCTYPE XML- ARTICLE (title, tm) ( : A short History of XML ™ ) ([]). :
<!DOCTYPE ARTICLE
[
<!ENTITY title "A short History of XML">
<!ENTITY tm " ™ " >
]
, DTD . (parameter entity), .. , DTD. (%), .
<! ENTITY % cdata "#CDATA">
XML DTD, . (&), (%):
%cdata;
() XML- ARTICLE. :
<!DOCTYPE ARTICLE SYSTEM "filename.dtd" [ <! ENTITY surname " "]>
(external entities)
XML- Topics.xml DTD filename.dtd:
<!DOCTYPE ARTICLE
[
<!ENTITY topics SYSTEM "Topics.xml">
]
topics - ( ). Topics.xml , , . (') (") , , .
(URI) , . URI , Internet-, (URL).
URI, :
<!ENTITY topics SYSTEM "http://bogus.com/documents/Topics.xml ">
URI, XML-, URI, :
|
|
|
<!ENTITY topics SYSTEM "Topics.xml">
Topics.xml ARTICLE.xml, &topics;
URI XML- URL HTML-.
(ENTITY) , (parsed) (unparsed) -.
XML- ( , ). , ( ), . XML () , . .
: XML- , , XML-. XML- (, ) (, ). XML, . , ENTITY ENTITIES, , .
, DTD XML- Faun.gif ( ) faun. (NOTATION) GIF. , GIF (ShowGif.exe). DTD COVERIMAGE ENTITY Source:
<?xml version="1.0" encoding="windows-1251"?>
<!DOCTYPE BOOK
[
<!ELEMENT BOOK (TITLE, AUTHOR, COVERIMAGE)>
<!ELEMENT TITLE (#PCDATA)>
<!ELEMENT AUTHOR (#PCDATA)>
<!ELEMENT COVERIMAGE EMPTY>
<!ATTLIST COVERIMAGE Source ENTITY #REQUIRED>
<!NOTATION GIF SYSTEM "ShowGif.exe">
<!ENTITY faun SYSTEM "Faun.gif" NDATA GIF>
]>
Source COVERIMAGE , . Source ENTITY, . ENTITY ENTITIES.
<BOOK>
<TITLE>The Marble Faun</TITLE>
<AUTHOR>Nathaniel Hawthorne</AUTHOR>
<COVERIMAGE Source="faun" />
</BOOK>
XML.
:
XML
|
|
|
, XML : , , , CDATA, , .
XML HTML , . XML. XML , - , "" , . , , XML:
1. "" ?
2. XML?
3. ?
4.
< Support id=1234 > SD > 12xz </ support >.
5.
< item selected > </ item >?
6. "" ?
7. , ?
8. ?
9. ?
10. ?
11. XML?
12. ?
13. ?
1. . . XML. - .: -, 2003. - 336 : .
..
