元素http://www.w3.org/2001/XMLSchema:complexType在此上下文中无效

Question

I'm trying to validate this XML file

<session>
    <mic id="1" posname="T1" x="0.0" y="0.0" z="0.0" />
</session>

using this XSD file

<?xml version="1.0" encoding="utf-8"?>
<xs:schema 
    xmlns:xs="http://www.w3.org/2001/XMLSchema" 
    attributeFormDefault="unqualified" 
    elementFormDefault="qualified">

    <xs:element name="session">
        <xs:complexType>
            <xs:sequence>
                <xs:element name="mic" type="micType" minOccurs="1" maxOccurs="4">
                </xs:element>

                <xs:complexType name="micType">
                    <xs:simpleContent>
                        <xs:extension base="xs:string">
                            <xs:attribute type="xs:int" name="id"/>
                            <xs:attribute type="xs:string" name="posname"/>
                            <xs:attribute type="xs:float" name="x"/>
                            <xs:attribute type="xs:float" name="y"/>
                            <xs:attribute type="xs:float" name="z"/>
                        </xs:extension>
                    </xs:simpleContent>
                </xs:complexType> 
            </xs:sequence>
        </xs:complexType>
    </xs:element>
</xs:schema>

but I get this error message:

XmlSchema error: Element http://www.w3.org/2001/XMLSchema:complexType is invalid in this context.

If I just have the attribute definition for the mic element the program runs fine. I don't know what I'm doing wrong. I'm trying to have the XSD validate the data types for the mic element. Can anybody please tell me what I'm doing wrong?

Answer 1

名为micType的complexType应定义为全局类型声明，即它应该是xs：schema元素的直接子节点。

Answer 2

What you have is a non-viable hybrid of a local and global declaration of a complex type. Either define a micType globally (as Michael Kay mentioned) or locally:

Global complexType declaration

<?xml version="1.0" encoding="utf-8"?>
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema" 
           attributeFormDefault="unqualified" 
           elementFormDefault="qualified">
  <xs:element name="session">
    <xs:complexType>
      <xs:sequence>
        <xs:element name="mic" type="micType" minOccurs="1" maxOccurs="4"/>
      </xs:sequence>
    </xs:complexType>
  </xs:element>
  <xs:complexType name="micType">
    <xs:simpleContent>
      <xs:extension base="xs:string">
        <xs:attribute type="xs:int" name="id"/>
        <xs:attribute type="xs:string" name="posname"/>
        <xs:attribute type="xs:float" name="x"/>
        <xs:attribute type="xs:float" name="y"/>
        <xs:attribute type="xs:float" name="z"/>
      </xs:extension>
    </xs:simpleContent>
  </xs:complexType>
</xs:schema>

Local complexType declaration

<?xml version="1.0" encoding="utf-8"?>
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema" 
           attributeFormDefault="unqualified" 
           elementFormDefault="qualified">
  <xs:element name="session">
    <xs:complexType>
      <xs:sequence>
        <xs:element name="mic" minOccurs="1" maxOccurs="4">
          <xs:complexType>
            <xs:simpleContent>
              <xs:extension base="xs:string">
                <xs:attribute type="xs:int" name="id"/>
                <xs:attribute type="xs:string" name="posname"/>
                <xs:attribute type="xs:float" name="x"/>
                <xs:attribute type="xs:float" name="y"/>
                <xs:attribute type="xs:float" name="z"/>
              </xs:extension>
            </xs:simpleContent>
          </xs:complexType>
        </xs:element>
      </xs:sequence>
    </xs:complexType>
  </xs:element>
</xs:schema>

Either way is ok and will successfully validate your XML.