Schema with xsd:any - XmlReader validation error

Question

I have problem with types in my schema when trying to use xsd:any element During validation i've got validation exception: The 'MerchantAccount' element is not declared.

The idea is to have ability to specify any properties and values within ExtendedProperties element. Please advice what am i doing wrong.

Part of the schema

...
<xsd:complexType name="ExtendedPropertiesType">
    <xsd:sequence>
      <xsd:any minOccurs="0" maxOccurs="unbounded" />
    </xsd:sequence>
</xsd:complexType>

<xsd:complexType name="ProcessorInstanceType">
  <xsd:all>
    <xsd:element name="Id" type="xsd:string" />
    <xsd:element name="Descriptor" type="xsd:string" />
    <xsd:element minOccurs="0" name="ExtendedProperties" type="ExtendedPropertiesType" />
  </xsd:all>
  <xsd:attribute name="name" type="xsd:string" />
</xsd:complexType>
...

Part of xml file:

...
<ProcessorInstance name="aaaa">
  <Id>37fc527b-2845-43d0-99ca-ac1ff6f0ed86</Id>
  <Descriptor>Test</Descriptor>

  <ExtendedProperties>
    <MerchantAccount>1111</MerchantAccount>
  </ExtendedProperties>
</ProcessorInstance>
...

Validation code:

private static XmlDocument loadConfigurationXml(FileInfo configFile)
    {
        //load schema
        var sr = new StringReader(Schemas.ConfigurationSchema);
        var schema = XmlSchema.Read(sr, (o, ea) => { throw ea.Exception; });
        //validate against the schema
        var schemas = new XmlSchemaSet();
        schemas.Add(schema);
        var readerSettings = new XmlReaderSettings
        {
            ValidationType = ValidationType.Schema, 
            ValidationFlags = XmlSchemaValidationFlags.ReportValidationWarnings,
            Schemas = schemas,
        };
        readerSettings.ValidationEventHandler += (o, ea)=>
        {
            throw new PaynetValidationException(
                string.Format("Invalid configuration file, see schema for details: {0}", 
                              ea.Message), 
                ea.Exception);
        };
        var reader = XmlReader.Create(configFile.FullName, readerSettings);
        //parse and validate config file
        while (reader.Read()){}

        var ret = new XmlDocument();
        if (configFile.Length != 0)
            ret.Load(configFile.FullName);

        return ret;
    }

Answer 1

This is because the default for the processContents attribute is strict. If you want that to validate when you don't have the schema for the elements, then use

<xs:any minOccurs="0" maxOccurs="unbounded" processContents="lax"/>

BTW, if you're designing this schema, I'd suggest you stay away from xs:all. It may sound like a good idea to allow elements to be entered in any order, but this can lead to ambiguous content models, and can drive the code processing the schema absolutely nuts.