未使用XSD验证XML元素

Question

I have a problem regarding XML validation through and XSD schema. Let's say I have the following structure:

<?xml version="1.0" encoding="utf-8"?>
  <Root xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
    <Category1>
      <Elementb>a</Elementb>
      <Element2>1</Element2>
      <Element3>1.0</Element3>
    </Category1>
    <Category2>
      <Element4>b</Element4>
      <Element5>c</Element5>
    </Category2>
 </Root>

And also the following schema:

<?xml version="1.0"?>
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"
elementFormDefault="unqualified">
  <xs:element name="Root">
    <xs:complexType>
      <xs:all>
        <xs:element name="Category1" type="category1Type" minOccurs="0"/>
        <xs:element name="Category2" type="category2Type" minOccurs="0"/>
      </xs:all>
    </xs:complexType>
  </xs:element>
  <xs:complexType name="category1Type">
    <xs:all>
      <xs:element name="Element1" type="xs:token" minOccurs="0"/>
      <xs:element name="Element2" type="xs:integer" minOccurs="0"/>
      <xs:element name="Element3" type="xs:decimal" minOccurs="0"/>
    </xs:all>
  </xs:complexType>
  <xs:complexType name="category2Type">
    <xs:all>
      <xs:element name="Element4" type="xs:token" minOccurs="0"/>
      <xs:element name="Element5" type="xs:token" minOccurs="0"/>
    </xs:all>
  </xs:complexType>
</xs:schema>

Ok, "Elementb" does not validate as it is not defined in the schema. This is on purpose. Let's assume we validate using the following code:

foreach (XmlNode rootNode in document)
{
  foreach (XmlNode category in rootNode)
  {
    foreach (XmlElement element in category)
    {
      document.Validate(ValidationCallBack, element);
    }
  }
}

Meaning I want the validation be undertaken element by element. The problem is that, with this scenario, not only <Elementb> throws an exception when calling Validate, but also the following elements within that category. Why is that? What am I missing? I thought that by using xs:all and minOccurs="0" , order does not matter, and since <Element1> is missing, <Element2> should validate as well. Any ideas? Thank you.

Answer 1

I think its because your just asking it to validate

 <Element2>1</Element2>

Its got no context of where element2 is in the document, so its treating it as the root element. Which is not valid against the XML schema as the only root element defined is 'Root'.

You maybe able to change the schema to look like this, but its more normal to validate the document from the root and deal with the results in the validation handler

<?xml version="1.0" encoding="utf-8" ?>
<!--Created with Liquid Studio 2018 (https://www.liquid-technologies.com)-->
<xs:schema elementFormDefault="unqualified"
           xmlns:xs="http://www.w3.org/2001/XMLSchema">
    <xs:element name="Root">
        <xs:complexType>
            <xs:all>
                <xs:element name="Category1"
                            type="category1Type"
                            minOccurs="0" />
                <xs:element name="Category2"
                            type="category2Type"
                            minOccurs="0" />
            </xs:all>
        </xs:complexType>
    </xs:element>
    <xs:complexType name="category1Type">
        <xs:all>
            <xs:element ref="Element1"
                        minOccurs="0" />
            <xs:element ref="Element2"
                        minOccurs="0" />
            <xs:element ref="Element3"
                        minOccurs="0" />
        </xs:all>
    </xs:complexType>
    <xs:complexType name="category2Type">
        <xs:all>
            <xs:element ref="Element4"
                        minOccurs="0" />
            <xs:element ref="Element5"
                        minOccurs="0" />
        </xs:all>
    </xs:complexType>
    <xs:element name="Element1"
                type="xs:token" />
    <xs:element name="Element2"
                type="xs:integer" />
    <xs:element name="Element3"
                type="xs:decimal" />
    <xs:element name="Element4"
                type="xs:token" />
    <xs:element name="Element5"
                type="xs:token" />
</xs:schema>