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XML Schema choice Element

Definition and Usage

XML Schema choice element allows only one of the elements contained in the <choice> declaration to be present within the containing element.

Element Information

Parent elements: group, choice, sequence, complexType, restriction (both simpleContent and complexContent), extension (both simpleContent and complexContent)

Syntax

(The ? sign declares that the element can occur zero or one time, and the * sign declares that the element can occur zero or more times inside the choice element)

Attribute	Description
id	Optional. Specifies a unique ID for the element
maxOccurs	Optional. Specifies the maximum number of times the choice element can occur in the parent element. The value can be any number >= 0, or if you want to set no limit on the maximum number, use the value "unbounded". Default value is 1
minOccurs	Optional. Specifies the minimum number of times the choice element can occur in the parent the element. The value can be any number >= 0. Default value is 1
any attributes	Optional. Specifies any other attributes with non-schema namespace

Example 1

<xs:element name="person">
  <xs:complexType>
    <xs:choice>
      <xs:element name="employee" type="employee"/>
      <xs:element name="member" type="member"/>
    </xs:choice>
  </xs:complexType>
</xs:element>

The example above defines an element named "person" which must contain either a "employee" element or a "member" element.

Complete XML Schema Reference