如何创建一个可以处理多个但类似的XML文件的XML Schema。例如，对于食谱食谱网站，我有一个名为'甜点'的食谱XML，另一个'印度'和另一个'素食'，它们几乎都是一样的，唯一改变的是根元素。这是一个文件示例：
<?xml version="1.0" encoding="utf-8"?>
<!-- this one could be dessert, indian or vegetarian -->
<dessert id="dessert01" xmlns="http://www.w3schools.com"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="schematize.xsd">
<category>Dessert</category>
<headline>Caramelised Bananas and Puff Pastry</headline>
<thumbnail>http://media.lookandtaste.com/files/video_thumbs/caramelized_banana_on_puff_pastry.jpg</thumbnail>
<intro>Most people are terrified of making desserts so this is one
that I invented to get you all out of that tricky situation...</intro>
<media>
<video><![CDATA[
<object type="application/x-shockwave-flash" data="http://www.lookandtaste.com//web/jwplayer/player.swf" width="480" height="292" ><param name="movie" value="http://www.lookandtaste.com//web/jwplayer/player.swf" /><param name="bgColor" value="#000000" /><param name="allowfullscreen" value="true" /><param name="allowScriptAccess" value="always" /><param name="FlashVars" value="stretching=exactfit&file=http://videos.lookandtaste.com/New_Vids/Caramelised Bananas and Puff Pastry_01.flv&image=http://www.lookandtaste.com/files/video_thumbs/caramelized_banana_on_puff_pastry.jpg"/></object>
]]>
</video>
</media>
<summary>
<preparation>10 minutes</preparation>
<time>20 minutes</time>
<difficulty>Medium</difficulty>
<healthy>2</healthy>
</summary>
<ingredients>
<ingredient>Puff pastry</ingredient>
<ingredient>Bananas</ingredient>
<ingredient>12 cups of sugar</ingredient>
<ingredient>Knob of butter</ingredient>
<ingredient>2 tsp of creme fraiche</ingredient>
<ingredient>1/2 cup of chocolate</ingredient>
</ingredients>
<procedures>
<step>Peel the bananas and chop into chunks. Put the butter and
bananas in a pan over a medium heat and sprinkle with sugar.
Caramelise for 4-5 minutes moving the ingredients every few minutes.</step>
<step>Meanwhile sprinkle flour onto a baking tray and also
onto a clean flat surface. Roll your pastry on the surface and then
cut out a circle shape using the top of a bowl as a cutter.</step>
<step>Put the pastry on the floured baking tray and prick the
pastry with a fork. Put the pastry into the over for 12-15 minutes at
180c/360f.</step>
<step>The bananas should be caramelised now so take them off the
heat and set them aside.</step>
<step>Take the pastry out of the oven once it is ready and pile
the bananas on top with some creme fraiche. Drizzle with melted
chocolate and serve.</step>
</procedures>
<keywords>banana hot caramel dessert</keywords>
</dessert>
...这是我的XML Schema文件：
<?xml version="1.0" encoding="UTF-8"?>
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"
elementFormDefault="qualified">
<xs:element name="dessert">
<xs:complexType>
<xs:sequence>
<xs:element ref="category"/>
<xs:element ref="headline"/>
<xs:element ref="thumbnail"/>
<xs:element ref="intro"/>
<xs:element ref="media"/>
<xs:element ref="summary"/>
<xs:element ref="ingredients"/>
<xs:element ref="procedures"/>
<xs:element ref="keywords"/>
</xs:sequence>
<xs:attribute name="id" use="required" type="xs:NCName"/>
</xs:complexType>
</xs:element>
<xs:element name="category" type="xs:NCName"/>
<xs:element name="headline" type="xs:string"/>
<xs:element name="thumbnail" type="xs:anyURI"/>
<xs:element name="intro" type="xs:string"/>
<xs:element name="media">
<xs:complexType>
<xs:sequence>
<xs:element ref="video"/>
</xs:sequence>
</xs:complexType>
</xs:element>
<xs:element name="video" type="xs:string"/>
<xs:element name="summary">
<xs:complexType>
<xs:sequence>
<xs:element ref="preparation"/>
<xs:element ref="time"/>
<xs:element ref="difficulty"/>
<xs:element ref="healthy"/>
</xs:sequence>
</xs:complexType>
</xs:element>
<xs:element name="preparation" type="xs:string"/>
<xs:element name="time" type="xs:string"/>
<xs:element name="difficulty" type="xs:NCName"/>
<xs:element name="healthy" type="xs:integer"/>
<xs:element name="ingredients">
<xs:complexType>
<xs:sequence>
<xs:element maxOccurs="unbounded" ref="ingredient"/>
</xs:sequence>
</xs:complexType>
</xs:element>
<xs:element name="ingredient" type="xs:string"/>
<xs:element name="procedures">
<xs:complexType>
<xs:sequence>
<xs:element maxOccurs="unbounded" ref="step"/>
</xs:sequence>
</xs:complexType>
</xs:element>
<xs:element name="step" type="xs:string"/>
<xs:element name="keywords" type="xs:string"/>
</xs:schema>
非常感谢指出可能的解决方案或如何处理它。提前谢谢！
答案 0 :(得分：2)
不只是：
<xs:complexType name="food">...</xs:complexType>
<xs:element type="food" name="dessert"/>
<xs:element type="food" name="indian"/>
答案 1 :(得分：1)
在为根元素编写模式时，需要指定“选择”指示符。由于大多数内容对于所有根元素都是通用的，因此您可以定义一个复杂类型，然后重复使用以避免再次编写它们。请参阅http://www.w3schools.com/schema/schema_complex_indicators.asp
[编辑]
如果您可以控制XML文档结构（即，如果它们未被其他应用程序使用），为什么不定义名为“food”的根元素并指定具有诸如“desert”和“indian”之类的值的可能属性foodType
答案 2 :(得分：0)
这是一种方法：
将架构元素更改为：
<xs:schema xmlns="urn:my.nampespace"
targetNamespace="urn:my.nampespace"
xmlns:xs="http://www.w3.org/2001/XMLSchema"
elementFormDefault="qualified">
将第一个元素更改为：
<xs:element name="dessert" type="recipeType"/>
<xs:element name="indian" type="recipeType"/>
<xs:complexType name="recipeType">
<xs:sequence>
<xs:element ref="category"/>
<xs:element ref="headline"/>
<xs:element ref="thumbnail"/>
<xs:element ref="intro"/>
<xs:element ref="media"/>
<xs:element ref="summary"/>
<xs:element ref="ingredients"/>
<xs:element ref="procedures"/>
<xs:element ref="keywords"/>
</xs:sequence>
<xs:attribute name="id" use="required" type="xs:NCName"/>
</xs:complexType>
现在您可以将xml定义为：
<dessert id="dessert01"
xmlns="urn:my.nampespace"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="urn:my.nampespace recipe.xsd">
或者：
<indian id="indian01"
xmlns="urn:my.nampespace"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="urn:my.nampespace recipe.xsd">
答案 3 :(得分：0)
kulfi怎么样？ （素食，印度甜点）
您可能不应该更改根元素，而是添加属性以指示类别。