[xml] How to make an element in XML schema optional?

So I got this XML schema:

<?xml version="1.0"?> <xs:schema version="1.0"
           xmlns:xs="http://www.w3.org/2001/XMLSchema"
           elementFormDefault="qualified">
    <xs:element name="request">
        <xs:complexType>
            <xs:sequence>
                <xs:element name="amenity">
                    <xs:complexType>
                        <xs:sequence>
                            <xs:element name="description" type="xs:string" />
                        </xs:sequence>
                    </xs:complexType>
                </xs:element>
            </xs:sequence>
        </xs:complexType>
    </xs:element> </xs:schema>

How do I make the description element optional? So both XML with the description element and without will validate against the XSD.

This question is related to xml xsd

The answer is


Try this

<xs:element name="description" type="xs:string" minOccurs="0" maxOccurs="1" />

if you want 0 or 1 "description" elements, Or

<xs:element name="description" type="xs:string" minOccurs="0" maxOccurs="unbounded" />

if you want 0 to infinity number of "description" elements.


Set the minOccurs attribute to 0 in the schema like so:

<?xml version="1.0"?>
  <xs:schema version="1.0" xmlns:xs="http://www.w3.org/2001/XMLSchema" elementFormDefault="qualified">
    <xs:element name="request">
        <xs:complexType>
            <xs:sequence>
                <xs:element name="amenity">
                    <xs:complexType>
                        <xs:sequence>
                            <xs:element name="description" type="xs:string" minOccurs="0" />
                        </xs:sequence>
                    </xs:complexType>
                </xs:element>
            </xs:sequence>
        </xs:complexType>
    </xs:element> </xs:schema>