Validation Using an Inline XML Schema with XmlReader

You can validate an XML file against an inline XML Schema definition language (XSD) schema. Before creating the XmlReader, change the XmlReaderSettings.ValidationFlags property to enable the ProcessInlineSchema option.

Example

The following example validates an XML file using an inline XML Schema. Because the reader is configured to display validation warnings, you also see the expected warning on the root element.

Imports System
Imports System.Xml
Imports System.Xml.Schema
Imports System.IO

public class ValidXSD 

  public shared sub Main() 

    ' Set the validation settings.
    Dim settings as XmlReaderSettings = new XmlReaderSettings()
    settings.ValidationType = ValidationType.Schema
    settings.ValidationFlags = settings.ValidationFlags Or XmlSchemaValidationFlags.ProcessInlineSchema
    settings.ValidationFlags = settings.ValidationFlags Or XmlSchemaValidationFlags.ReportValidationWarnings
      AddHandler settings.ValidationEventHandler, AddressOf ValidationCallBack

    ' Create the XmlReader object.
    Dim reader as XmlReader = XmlReader.Create("inlineSchema.xml", settings)

    ' Parse the file. 
    while (reader.Read())
    end while
  end sub

  ' Display any warnings or errors.
  private shared sub ValidationCallBack (sender as object, args as ValidationEventArgs)
     if (args.Severity=XmlSeverityType.Warning)
       Console.WriteLine("   Warning: Matching schema not found.  No validation occurred." + args.Message)
     else
        Console.WriteLine("   Validation error: " + args.Message)
     end if
  end sub 

end class 

using System;
using System.Xml;
using System.Xml.Schema;
using System.IO;

public class ValidXSD {

  public static void Main() {

    // Set the validation settings.
    XmlReaderSettings settings = new XmlReaderSettings();
    settings.ValidationType = ValidationType.Schema;
    settings.ValidationFlags |= XmlSchemaValidationFlags.ProcessInlineSchema;
    settings.ValidationFlags |= XmlSchemaValidationFlags.ReportValidationWarnings;
    settings.ValidationEventHandler += new ValidationEventHandler (ValidationCallBack);

    // Create the XmlReader object.
    XmlReader reader = XmlReader.Create("inlineSchema.xml", settings);

    // Parse the file. 
    while (reader.Read());

  }

  // Display any warnings or errors.
  private static void ValidationCallBack (object sender, ValidationEventArgs args) {
     if (args.Severity==XmlSeverityType.Warning)
       Console.WriteLine("\tWarning: Matching schema not found.  No validation occurred." + args.Message);
     else
        Console.WriteLine("\tValidation error: " + args.Message);

  }  

}

Input

The example uses the inlineSchema.xml file as input.

<root>
<!--Start of schema-->
<xs:schema xmlns:xs='http://www.w3.org/2001/XMLSchema'
            xmlns='xsdHeadCount'
            targetNamespace='xsdHeadCount'>
    <xs:element name='HeadCount'>
        <xs:complexType>
            <xs:sequence>
                <xs:element name='ID' type='xs:unsignedShort' maxOccurs='unbounded' />
            </xs:sequence>
            <xs:attribute name='division' type='xs:string' use='optional' default='QA'/>
        </xs:complexType>
    </xs:element>
</xs:schema>
<!--End of schema-->
<hc:HeadCount xmlns:hc='xsdHeadCount'>
    <ID>12365</ID>
    <ID>43295</ID>
    <division>Accounting</division>
</hc:HeadCount>
</root>

Output

Warning:   Matching schema not found. No validation occurred. Could not find schema information for the element 'root'.

Validation error:   The element 'xsdHeadCount:HeadCount' has invalid child element 'division'. Expected 'ID'.

See Also

Concepts

Reading XML with the XmlReader

Other Resources

Validating XML Data with XmlReader