xml&dtd的例子

一个xml的例子，后面还有解析的部分

<?xml version="1.0" encoding="UTF-8"?>
<!ELEMENT class (teacher,student+)>
<!ELEMENT teacher (name, main-subject*)>
<!ELEMENT main-subject (#PCDATA)>
<!ATTLIST teacher teacher-id CDATA #REQUIRED>
<!ELEMENT name (first-name, family-name)>
<!ELEMENT first-name (#PCDATA)>
<!ELEMENT family-name (#PCDATA)>
<!ELEMENT student (name, age, gender)>
<!ATTLIST student student-id CDATA #REQUIRED>
<!ELEMENT age (#PCDATA)>
<!ELEMENT gender (#PCDATA)>

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE class SYSTEM "class.dtd">
<class>
<teacher teacher-id="1">
	<name>
		<first-name>Hongling</first-name>
		<family-name>Chang</family-name>
	</name>
	<main-subject>Chinese</main-subject>
	<main-subject>English</main-subject>
</teacher>
<student student-id="001">
	<name>
		<first-name>Xiangzhong</first-name>
		<family-name>Chang</family-name>
	</name>
	<age>21</age>
	<gender>male</gender>
</student>
</class>