15.2.45. XML Schema list element

发布时间 :2025-10-25 12:23:22 UTC      

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Definition and usage

The list element defines a collection of individual simpleType definitions.

Element information

  • 父元素: SimpleType

Grammar

<list
id=ID
itemType=QName
*any attributes*
>
(annotation?,(simpleType?))
</list>

(? Symbol declaration an element can appear zero or once in a list element. )

Attribute

Description

Id

Optional. Specifies the unique ID of the element.

ItemType

The name of the built-in data type or simpleType element defined in this schema (or other schema indicated by the specified namespace). The simpleType element that contains the list element is derived from the simple type specified by the list value. The list value must be a qualified name (QName). This attribute is not allowed if the content contains a simpleType element, otherwise it is required.

Any attributes

Optional. Specifies any other attributes with the non-schema namespace.

Example 1

The following example shows a simple type that is a column of integers:

<?xml version="1.0"?>
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema">
<xs:element name="intvalues" type="valuelist">
<xs:simpleType name="valuelist">
  <xs:list itemType="xs:integer"/>
</xs:simpleType>
</xs:schema>
文档中的 "intvalues" 元素类似这样(注意这个列表有五个列表项):
<intvalues>100 34 56 -23 1567</intvalues>

注意: Spaces are used as delimiters for list items.

Example 2

The following example shows a simple type for a column of strings:

<?xml version="1.0"?>
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema">
<xs:element name="stringvalues" type="valuelist">
<xs:simpleType name="valuelist">
  <xs:list itemType="xs:string"/>
</xs:simpleType>
</xs:schema>
文档中的 "stringvalues" 元素类似这样(注意这个列表有四个列表项):
<stringvalues>I love XML Schema</stringvalues>

XML Schema 参考手册 完整 XML Schema 参考手册

Principles, Technologies, and Methods of Geographic Information Systems  102

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.