readme.txt

xml文件处理多平台类

/** @mainpage

<h1> TinyXml </h1>

TinyXml is a simple, small, C++ XML parser that can be easily 
integrating into other programs.


<h2> What it does. </h2>
	
In brief, TinyXml parses an XML document, and builds from that a 
Document Object Model (DOM) that can be read, modified, and saved.

XML stands for "eXtensible Markup Language." It allows you to create 
your own document markups. Where HTML does a very good job of marking 
documents for browsers, XML allows you to define any kind of document 
markup, for example a document that describes a "to do" list for an 
organizer application. XML is a very structured and convenient format.
All those random file formats created to store application data can 
all be replaced with XML. One parser for everything.

The best place for the complete, correct, and quite frankly hard to
read spec is at <a href="http://www.w3.org/TR/2004/REC-xml-20040204/">
http://www.w3.org/TR/2004/REC-xml-20040204/</a>. An intro to XML
(that I really like) can be found at 
<a href="http://skew.org/xml/tutorial/">http://skew.org/xml/tutorial</a>.

There are different ways to access and interact with XML data.
TinyXml uses a Document Object Model (DOM), meaning the XML data is parsed
into a C++ objects that can be browsed and manipulated, and then 
written to disk or another output stream. You can also construct an XML document from
scratch with C++ objects and write this to disk or another output
stream.

TinyXml is designed to be easy and fast to learn. It is two headers 
and four cpp files. Simply add these to your project and off you go. 
There is an example file - xmltest.cpp - to get you started. 

TinyXml is released under the ZLib license, 
so you can use it in open source or commercial code. The details
of the license are at the top of every source file.

TinyXml attempts to be a flexible parser, but with truly correct and
compliant XML output. TinyXml should compile on any reasonably C++
compliant system. It does not rely on exceptions or RTTI. It can be 
compiled with or without STL support. TinyXml fully supports
the UTF-8 encoding, and the first 64k character entities.


<h2> What it doesn't do. </h2>

It doesnt parse or use DTDs (Document Type Definitions) or XSLs
(eXtensible Stylesheet Language.) There are other parsers out there 
(check out www.sourceforge.org, search for XML) that are much more fully
featured. But they are also much bigger, take longer to set up in
your project, have a higher learning curve, and often have a more
restrictive license. If you are working with browsers or have more
complete XML needs, TinyXml is not the parser for you.

The following DTD syntax will not parse at this time in TinyXml:

@verbatim
	<!DOCTYPE Archiv [
	 <!ELEMENT Comment (#PCDATA)>
	]>
@endverbatim

because TinyXml sees this as a !DOCTYPE node with an illegally 
embedded !ELEMENT node. This may be addressed in the future.

<h2> Code Status.  </h2>

TinyXml is mature, tested code. It is very stable. If you find
bugs, please file a bug report is on the sourceforge web site
(www.sourceforge.net/projects/tinyxml).
We'll get them straightened out as soon as possible.

There are some areas of improvement; please check sourceforge if you are
interested in working on TinyXml.


<h2> Features </h2>

<h3> Using STL </h3>

TinyXml can be compiled to use or not use STL. When using STL, TinyXml
uses the std::string class, and fully supports std::istream, std::ostream,
operator<<, and operator>>. Many API methods have both 'const char*' and
'const std::string&' forms.

When STL support is compiled out, no STL files are included whatsover. All
the string classes are implemented by TinyXml itself. API methods
all use the 'const char*' form for input.

Use the compile time #define:

	TIXML_USE_STL

to compile one version or the other. This can be passed by the compiler,
or set as the first line of "tinyxml.h".

Note: If compiling the test code in Linux, setting the environment
variable TINYXML_USE_STL=YES/NO will control STL compilation. In the
Windows project file, STL and non STL targets are provided. In your project,
its probably easiest to add the line "#define TIXML_USE_STL" as the first
line of tinyxml.h.

<h3> UTF-8 </h3>

TinyXml supports UTF-8 allowing to manipulate XML files in any language. TinyXml
also supports "legacy mode" - the encoding used before UTF-8 support and
probably best described as "extended ascii".

Normally, TinyXml will try to detect the correct encoding and use it. However,
by setting the value of TIXML_DEFAULT_ENCODING in the header file, TinyXml
can be forced to always use one encoding.

TinyXml will assume Legacy Mode until one of the following occurs:
<ol>
	<li> If the non-standard but common "UTF-8 lead bytes" (0xef 0xbb 0xbf)
		 begin the file or data stream, TinyXml will read it as UTF-8. </li>
	<li> If the declaration tag is read, and it has an encoding="UTF-8", then
		 TinyXml will read it as UTF-8. </li>
	<li> If the declaration tag is read, and it has no encoding specified, then
		 TinyXml will read it as UTF-8. </li>
	<li> If the declaration tag is read, and it has an encoding="something else", then
		 TinyXml will read it as Legacy Mode. In legacy mode, TinyXml will 
		 work as it did before. It's not clear what that mode does exactly, but 
		 old content should keep working.</li>
	<li> Until one of the above criteria is met, TinyXml runs in Legacy Mode.</li>
</ol>

What happens if the encoding is incorrectly set or detected? TinyXml will try
to read and pass through text seen as improperly encoded. You may get some strange
results or mangled characters. You may want to force TinyXml to the correct mode.

<b> You may force TinyXml to Legacy Mode by using LoadFile( TIXML_ENCODING_LEGACY ) or
LoadFile( filename, TIXML_ENCODING_LEGACY ). You may force it to use legacy mode all
the time by setting TIXML_DEFAULT_ENCODING = TIXML_ENCODING_LEGACY. Likewise, you may 
force it to TIXML_ENCODING_UTF8 with the same technique.</b>

For English users, using English XML, UTF-8 is the same as low-ASCII. You
don't need to be aware of UTF-8 or change your code in any way. You can think
of UTF-8 as a "superset" of ASCII.

UTF-8 is not a double byte format - but it is a standard encoding of Unicode!
TinyXml does not use or directly support wchar, TCHAR, or Microsofts _UNICODE at this time. 
It is common to see the term "Unicode" improperly refer to UTF-16, a wide byte encoding
of unicode. This is a source of confusion.

For "high-ascii" languages - everything not English, pretty much - TinyXml can
handle all languages, at the same time, as long as the XML is encoded
in UTF-8. That can be a little tricky, older programs and operating systems
tend to use the "default" or "traditional" code page. Many apps (and almost all
modern ones) can output UTF-8, but older or stubborn (or just broken) ones
still output text in the default code page. 

For example, Japanese systems traditionally use SHIFT-JIS encoding. 
Text encoded as SHIFT-JIS can not be read by tinyxml. 
A good text editor can import SHIFT-JIS and then save as UTF-8.

The <a href="http://skew.org/xml/tutorial/">Skew.org link</a> does a great
job covering the encoding issue.

The test file "utf8test.xml" is an XML containing English, Spanish, Russian,
and Simplified Chinese. (Hopefully they are translated correctly). The file
"utf8test.gif" is a screen capture of the XML file, rendered in IE. Note that
if you don't have the correct fonts (Simplified Chinese or Russian) on your
system, you won't see output that matches the GIF file even if you can parse
it correctly. Also note that (at least on my Windows machine) console output
is in a Western code page, so that Print() or printf() cannot correctly display
the file. This is not a bug in TinyXml - just an OS issue. No data is lost or 
destroyed by TinyXml. The console just doesn't render UTF-8.


<h3> Entities </h3>
TinyXml recognizes the pre-defined "character entities", meaning special
characters. Namely:

@verbatim
	&amp;	&
	&lt;	<
	&gt;	>
	&quot;	"
	&apos;	'
@endverbatim

These are recognized when the XML document is read, and translated to there
UTF-8 equivalents. For instance, text with the XML of:

@verbatim
	Far &amp; Away
@endverbatim

will have the Value() of "Far & Away" when queried from the TiXmlText object,
and will be written back to the XML stream/file as an ampersand. Older versions
of TinyXml "preserved" character entities, but the newer versions will translate
them into characters.

Additionally, any character can be specified by its Unicode code point:
The syntax "&#xA0;" or "&#160;" are both to the non-breaking space characher.


<h3> Streams </h3>
With TIXML_USE_STL on,
TiXml has been modified to support both C (FILE) and C++ (operator <<,>>) 
streams. There are some differences that you may need to be aware of.

C style output:
	- based on FILE*
	- the Print() and SaveFile() methods

	Generates formatted output, with plenty of white space, intended to be as 
	human-readable as possible. They are very fast, and tolerant of ill formed 
	XML documents. For example, an XML document that contains 2 root elements 
	and 2 declarations, will still print.

C style input:
	- based on FILE*
	- the Parse() and LoadFile() methods

	A fast, tolerant read. Use whenever you don't need the C++ streams.

C++ style ouput:
	- based on std::ostream
	- operator<<

	Generates condensed output, intended for network transmission rather than
	readability. Depending on your system's implementation of the ostream class,
	these may be somewhat slower. (Or may not.) Not tolerant of ill formed XML:
	a document should contain the correct one root element. Additional root level
	elements will not be streamed out.

C++ style input:
	- based on std::istream
	- operator>>

	Reads XML from a stream, making it useful for network transmission. The tricky
	part is knowing when the XML document is complete, since there will almost
	certainly be other data in the stream. TinyXml will assume the XML data is
	complete after it reads the root element. Put another way, documents that
	are ill-constructed with more than one root element will not read correctly.
	Also note that operator>> is somewhat slower than Parse, due to both 
	implementation of the STL and limitations of TinyXml.

<h3> White space </h3>
The world simply does not agree on whether white space should be kept, or condensed.
For example, pretend the '_' is a space, and look at "Hello____world". HTML, and 
at least some XML parsers, will interpret this as "Hello_world". They condense white