如何使XML模式中的元素可选?

So I got this XML schema:

我得到了这个XML模式

<?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.

如何使description元素可选?因此，带有description元素的XML和不带有description元素的XML都将对XSD进行验证。

2 个解决方案

#1

148

Try this

试试这个

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

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

如果您想要0或1“description”元素，或

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

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

如果你想要0到无穷大数量的“描述”元素。

#2

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

在模式中设置minOccurs属性为0:

<?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>

#1

148