xml_约束_dtd 和 xml_约束_schema
作者:互联网
分类
DTD:一种简单的约束技术
Schema:一种复杂的约束技术
DTD
引入dtd文档到xml文档中
内部:dtd:将约束规则定义在xml文档中
外部:dtd:将约束规则定义在外部的dtd文件中
本地<!DOCTYPE 根标签 名 SYSTEM "dtd文件的位置">
网络<!DOCTYPE 根标签 名 PUBLIC "dtd文件名字" "dtd文件的位置url">
<?xml version="1.0" encoding="UTF-8" ?> <!DOCTYPE students SYSTEM "student.dtd"> <!--<!DOCTYPE students [--> <!-- <!ELEMENT students (student+) >--> <!-- <!ELEMENT student (name,age,sex)>--> <!-- <!ELEMENT name (#PCDATA)>--> <!-- <!ELEMENT age (#PCDATA)>--> <!-- <!ELEMENT sex (#PCDATA)>--> <!-- <!ATTLIST student number ID #REQUIRED>--> <!-- ]>--> <students> <student number="s001"> <name>zhangsan</name> <age>23</age> <sex>male</sex> </student> <student number="s002"> <name>lisi</name> <age>24</age> <sex>female</sex> </student> </students>
<!ELEMENT students (student+) > <!ELEMENT student (name,age,sex)> <!ELEMENT name (#PCDATA)> <!ELEMENT age (#PCDATA)> <!ELEMENT sex (#PCDATA)> <!ATTLIST student number ID #REQUIRED>
xml_约束_schema
填写xml文档的根元素
引入xsi前缀.xmlns:xsi="http: / / www. w3.org/2001/xNLSchema-instance"
引入xsd文件命名空间. xsi:schemaLocation="http: / /www.itcast.cn/xml student.xsd"
为每一个xsd约束声明一个前缀,作为标识xmlns="http://www.itcast.cn/xml"
<students xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns="http://www.itcast.cn/xml"
xsi:schemaLocation="http://www.itcast.cn/xml student.xsd">
<?xml version="1.0" encoding="UTF-8" ?> <students xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://www.itcast.cn/xml" xsi:schemaLocation="http://www.itcast.cn/xml student.xsd"> <student number="heima_0001"> <name>zhangsan</name> <age>11</age> <sex>male</sex> </student> <student number="heima_0002"> <name>wangwi</name> <age>14</age> <sex>female</sex> </student> </students>
<?xml version="1.0"?> <xsd:schema xmlns="http://www.itcast.cn/xml" xmlns:xsd="http://www.w3.org/2001/XMLSchema" targetNamespace="http://www.itcast.cn/xml" elementFormDefault="qualified"> <xsd:element name="students" type="studentsType"/> <xsd:complexType name="studentsType"> <xsd:sequence> <xsd:element name="student" type="studentType" minOccurs="0" maxOccurs="unbounded"/> </xsd:sequence> </xsd:complexType> <xsd:complexType name="studentType"> <xsd:sequence> <xsd:element name="name" type="xsd:string"/> <xsd:element name="age" type="ageType" /> <xsd:element name="sex" type="sexType" /> </xsd:sequence> <xsd:attribute name="number" type="numberType" use="required"/> </xsd:complexType> <xsd:simpleType name="sexType"> <xsd:restriction base="xsd:string"> <xsd:enumeration value="male"/> <xsd:enumeration value="female"/> </xsd:restriction> </xsd:simpleType> <xsd:simpleType name="ageType"> <xsd:restriction base="xsd:integer"> <xsd:minInclusive value="0"/> <xsd:maxInclusive value="256"/> </xsd:restriction> </xsd:simpleType> <xsd:simpleType name="numberType"> <xsd:restriction base="xsd:string"> <xsd:pattern value="heima_\d{4}"/> </xsd:restriction> </xsd:simpleType> </xsd:schema>
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标签:xml,www,http,--,约束,dtd,schema 来源: https://www.cnblogs.com/12-12-12/p/16557081.html