分析DTD文档，写XML实例（简单；自我讲解）

DTD文档如下：

文档名称：Newspaper.dtd 

<?xml version="1.0" encoding="UTF-8"?>
<!ELEMENT NEWSPAPER (ARTICLE+)> 
<!-- 上面这句表明根元素为NEWSPAPER，该元素里面至少有一个ARTICLE元素 --> 
<!ELEMENT ARTICLE (HEADLINE, BYLINE, LEAD, BODY, NOTES)>
<!-- 上面这句表明ARTICLE元素下有五个元素，依次为HEADLINE, BYLINE, LEAD, BODY, NOTES -->  
<!ELEMENT HEADLINE (#PCDATA)>
<!ELEMENT BYLINE (#PCDATA)>
<!ELEMENT LEAD (#PCDATA)>
<!ELEMENT BODY (#PCDATA)>
<!ELEMENT NOTES (#PCDATA)>
<!-- 上面这五句可以看出五个元素被定义为字符串类型 --> 


<!ATTLIST ARTICLE AUTHOR CDATA #REQUIRED>
<!-- 上面这句可以看出ARTICLE的AUTHOR参数是不可或缺的 -->  
<!ATTLIST ARTICLE EDITOR CDATA #IMPLIED>
<!ATTLIST ARTICLE DATE CDATA #IMPLIED>
<!ATTLIST ARTICLE EDITION CDATA #IMPLIED>
<!-- 上面这三句可以看出这三个ARTICLE的参数是可选的 -->  

XML实例： 

 文档名称：Newspaper.xml

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE NEWSPAPER SYSTEM "Newspaper.dtd">
<NEWSPAPER>
        <ARTICLE AUTHOR="梅夫">
                <HEADLINE/>
                <BYLINE/>
                <LEAD/>
                <BODY/>
                <NOTES/>
        </ARTICLE>
 
        <ARTICLE AUTHOR="雷杰">
                <HEADLINE/>
                <BYLINE/>
                <LEAD/>
                <BODY/>
                <NOTES/>
          </ARTICLE>
</NEWSPAPER>