XML Schema 参考手册 完整 XML Schema 参考手册 The attributeGroup element is used to combine attribute declarations so that they can be combined into complex types. 父元素: AttributeGroup, complexType, schema, restriction (both simpleContent and complexContent), extension (both simpleContent and complexContent) (? Symbol declaration in the attributeGroup element, the element can appear zero or once, and the* symbol declares that the element can appear zero or more times. ) Attribute Description Id Optional. Specifies the unique ID of the element. Name Optional. Specifies the name of the property group. The name and ref properties cannot appear at the same time. Ref Optional. Specifies a reference to the specified property group. The name and ref properties cannot appear at the same time. Any attributes Optional. Specifies any other attributes with the non-schema namespace. The above example defines a property group named “personattr”, which is used in a complex type named “person”. XML Schema 参考手册 完整 XML Schema 参考手册
In recent years, Geographic Information Systems (GIS) have undergone rapid development in both theoretical and practical dimensions. GIS has been widely applied for modeling and decision-making support across various fields such as urban management, regional planning, and environmental remediation, establishing geographic information as a vital component of the information era. The introduction of the “Digital Earth” concept has further accelerated the advancement of GIS, which serves as its technical foundation. Concurrently, scholars have been dedicated to theoretical research in areas like spatial cognition, spatial data uncertainty, and the formalization of spatial relationships. This reflects the dual nature of GIS as both an applied technology and an academic discipline, with the two aspects forming a mutually reinforcing cycle of progress. Definition and usage ¶
Element information ¶
Grammar ¶
Example 1 ¶
<xs:attributeGroup name="personattr">
<xs:attribute name="attr1" type="string"/>
<xs:attribute name="attr2" type="integer"/>
xs:attributeGroup>
<xs:complexType name="person">
<xs:attributeGroup ref="personattr"/>
xs:complexType>
Principles, Technologies, and Methods of Geographic Information Systems
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