XML Schema union Element
 Complete XML Schema Reference
Definition and Usage
The union element defines a simple type as a collection (union) of values
from specified simple data types.
Element Information
- Parent elements: simpleType
Syntax
<union
id=ID
memberTypes="list of QNames"
any attributes
>
(annotation?,(simpleType*))
</union>
|
(The ? sign declares that the element can occur zero or one time inside the
union element)
| Attribute |
Description |
| id |
Optional. Specifies a unique ID for the element |
| memberTypes |
Optional. Specifies a list of built-in data types or
simpleType elements defined in a schema |
| any attributes |
Optional. Specifies any other attributes with non-schema
namespace |
Example 1
This example shows a simple type that is a union of two simple types:
<xs:element name="jeans_size">
<xs:simpleType>
<xs:union memberTypes="sizebyno sizebystring" />
</xs:simpleType>
</xs:element>
<xs:simpleType name="sizebyno">
<xs:restriction base="xs:positiveInteger">
<xs:maxInclusive value="42"/>
</xs:restriction>
</xs:simpleType>
<xs:simpleType name="sizebystring">
<xs:restriction base="xs:string">
<xs:enumeration value="small"/>
<xs:enumeration value="medium"/>
<xs:enumeration value="large"/>
</xs:restriction>
</xs:simpleType>
|
Complete XML Schema Reference
 |
W3Schools' Online Certification Program
The perfect solution for professionals who need to balance work, family, and career building.
More than 4000 certificates already issued!
|
The HTML Certificate documents your knowledge of HTML, XHTML, and CSS.
The JavaScript Certificate documents your knowledge of JavaScript and HTML DOM.
The XML Certificate documents your knowledge of XML, XML DOM and XSLT.
The ASP Certificate documents your knowledge of ASP, SQL, and ADO.
The PHP Certificate documents your knowledge of PHP and SQL (MySQL).
| 
