XmlValidatingReader Class

Provides validation against an XML schema while reading an XML document.

Syntax

public class XmlValidatingReader : XmlReader

Remarks

The XmlValidatingReader class provides a way to perform validation against an XML Schema Definition (XSD) or Document Type Definition (DTD) as an XML document is being read. It wraps an existing XmlReader and adds validation capabilities.

When you instantiate XmlValidatingReader, you can specify an XmlReader to read from and an optional validation type (e.g., ValidationType.Schema for XSD or ValidationType.DTD for DTD). You can then set the schema to validate against using the Schema property.

The validation errors are reported through the ValidationEventHandler. You must attach an event handler to this event to receive validation warnings and errors.

Note: It is recommended to use the XmlReader.Create method with a XmlReaderSettings object to create an XmlReader that performs schema validation. This approach is more flexible and generally preferred over using XmlValidatingReader directly.

Methods

Name	Description
Close()	Closes this stream and underlying streams.
GetReaderAttribute(string name)	Gets the value of the attribute with the specified name.
GetReaderState()	Gets the state of the reader.
MoveToElement()	Moves the XmlReader to the element that has the specified attribute.
Read()	Moves the XmlReader to the next node.
ReadAttributeValue()	Reads the value of the current attribute node.
ReadContentAsBase64(byte[] buffer, int index, int count)	Reads the content of the current node as Base64 encoded data.
ReadContentAsBinHex(byte[] buffer, int index, int count)	Reads the content of the current node as BinHex encoded data.
ReadContentAsBoolean()	Reads the content of the current node as a Boolean.
ReadContentAsDateTime()	Reads the content of the current node as a DateTime.
ReadContentAsDecimal()	Reads the content of the current node as a Decimal.
ReadContentAsDouble()	Reads the content of the current node as a Double.
ReadContentAsInt()	Reads the content of the current node as an Int32.
ReadContentAsLong()	Reads the content of the current node as an Int64.
ReadContentAsObject()	Reads the content of the current node as an Object.
ReadContentAsQName(string[] prefixes, string[] namespaces)	Reads the content of the current node as a qualified name.
ReadContentAsString()	Reads the content of the current node as a string.
ReadContentAsUnsignedInt()	Reads the content of the current node as a UInt32.
ReadContentAsUnsignedLong()	Reads the content of the current node as a UInt64.
ReadElementContentAsBase64(byte[] buffer, int index, int count)	Reads the content of an element as Base64 encoded data.
ReadElementContentAsBinHex(byte[] buffer, int index, int count)	Reads the content of an element as BinHex encoded data.
ReadElementContentAsBoolean()	Reads the content of an element as a Boolean.
ReadElementContentAsDateTime()	Reads the content of an element as a DateTime.
ReadElementContentAsDecimal()	Reads the content of an element as a Decimal.
ReadElementContentAsDouble()	Reads the content of an element as a Double.
ReadElementContentAsInt()	Reads the content of an element as an Int32.
ReadElementContentAsLong()	Reads the content of an element as an Int64.
ReadElementContentAsObject()	Reads the content of an element as an Object.
ReadElementContentAsQName(string[] prefixes, string[] namespaces)	Reads the content of an element as a qualified name.
ReadElementContentAsString()	Reads the content of an element as a string.
ReadElementContentAsUnsignedInt()	Reads the content of an element as a UInt32.
ReadElementContentAsUnsignedLong()	Reads the content of an element as a UInt64.
ReadInnerXml()	Reads the inner XML of the current node and returns it as a string.
ReadOuterXml()	Reads the outer XML of the current node and returns it as a string.
ReadElementString()	Reads the text content of the current node and returns it as a string.
ReadSubtree()	Reads the rest of the current node, including all its descendants, and returns it as a new XmlReader.
ResolveEntity()	Resolves the entity in the DTD.

Properties

Name	Description
AttributeCount	Gets the number of attributes on the current node.
BaseURI	Gets the base URI of the current node.
CanResolveEntity	Gets a value indicating whether the reader can resolve entities.
CharsetSettings	Gets the character set information for the current document.
CheckOutDate	Gets the date of checkout.
CheckOutNumber	Gets the checkout number.
CheckOutStatus	Gets the checkout status.
CheckOutUser	Gets the checkout user.
ClaimDate	Gets the date of claim.
ClaimNumber	Gets the claim number.
ClaimStatus	Gets the claim status.
ClaimUser	Gets the claim user.
CommentValue	Gets the value of the comment.
Data	Gets the data.
Depth	Gets the depth of the current node in the XML document.
DisableUiDevices	Gets or sets a value that indicates whether UI devices are disabled.
Document	Gets the XmlDocument.
DocType	Gets the XmlDocumentType.
Encoding	Gets the encoding of the current XML declaration.
EOF	Gets a value indicating whether the reader is at the end of the stream.
HasAttributes	Gets a value indicating whether the current node has attributes.
HasValue	Gets a value indicating whether the node has a value.
IsDefault	Gets a value indicating whether the attribute is defaulted.
IsLocalName	Gets a value indicating whether the local name is the same as the attribute name.
IsXmlns	Gets a value indicating whether the attribute is an XML namespace attribute.
Item(int i)	Gets the value of the attribute with the specified index.
Item(string name)	Gets the value of the attribute with the specified name.
Item(string localName, string namespaceURI)	Gets the value of the attribute with the specified local name and namespace URI.
Lang	Gets the xml:lang attribute value of the current node.
LocalName	Gets the local name of the current node.
LogicalDirectory	Gets the logical directory.
MasterData	Gets the master data.
Name	Gets the qualified name of the current node.
NamespaceURI	Gets the namespace URI of the current node.
NamespaceManager	Gets the XmlNamespaceManager.
NamespaceManagerId	Gets the ID of the namespace manager.
NamespaceManagerMode	Gets the mode of the namespace manager.
NodeCount	Gets the total number of nodes read so far.
NodeLatency	Gets the latency of the node.
NodeType	Gets the type of the current node.
NormalizationForm	Gets a value indicating the normalization form to use.
Prefix	Gets the namespace prefix of the current node.
ProcessData	Gets the process data.
ProcessDefinition	Gets the process definition.
ProcessDefinitionId	Gets the process definition ID.
ProcessDefinitionName	Gets the process definition name.
ProcessId	Gets the process ID.
ProcessName	Gets the process name.
ProcessType	Gets the process type.
ProcessingInstructions	Gets the processing instructions.
ProcessVersion	Gets the process version.
Quotas	Gets the quotas.
Reader	Gets the underlying XmlReader.
ReadState	Gets the state of the reader.
Root	Gets the root element.
Schema	Gets or sets the schema collection to use for validation.
SchemaCollection	Gets the collection of schemas.
SkipWhitespace	Gets or sets a value indicating whether to skip whitespace.
State	Gets the state of the reader.
Stream	Gets the stream.
SuppressWhitespace	Gets or sets a value indicating whether to suppress whitespace.
ValidationEventHandler	Gets or sets the delegate that handles validation events.
ValidationType	Gets or sets the type of validation to perform.
Value	Gets the value of the current node.
Values	Gets the values.
XmlBaseURI	Gets the base URI of the current node.
XmlCharCount	Gets the character count.
XmlEncoding	Gets the XML encoding.
XmlFileCount	Gets the file count.
XmlFilePath	Gets the file path.
XmlFileType	Gets the file type.
XmlFileSize	Gets the file size.
XmlFileSizeInBytes	Gets the file size in bytes.
XmlFileTypeId	Gets the file type ID.
XmlFileTypeName	Gets the file type name.
XmlIndent	Gets or sets a value indicating whether to indent the XML.
XmlItemCount	Gets the item count.
XmlName	Gets the XML name.
XmlNamespace	Gets the XML namespace.
XmlNamespaceURI	Gets the XML namespace URI.
XmlNodeCount	Gets the node count.
XmlPrefix	Gets the XML prefix.
XmlString	Gets the XML string.
XmlVersion	Gets the XML version.

Events

Name	Description
ValidationEventHandler	Fired when a validation warning or error occurs.

Examples

Validating an XML Document with an XSD Schema

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

public class Example
{
    public static void Main(string[] args)
    {
        // Create an XmlReader to read the XML document
        XmlReader reader = XmlReader.Create("myDocument.xml");

        // Create an XmlValidatingReader
        XmlValidatingReader validatingReader = new XmlValidatingReader(reader);

        // Load the XSD schema
        XmlSchemaSet schemaSet = new XmlSchemaSet();
        schemaSet.Add(null, "mySchema.xsd");
        validatingReader.Schemas.Add(schemaSet);

        // Set the validation type to Schema
        validatingReader.ValidationType = ValidationType.Schema;

        // Add a handler for validation events
        validatingReader.ValidationEventHandler += new ValidationEventHandler(ValidationCallBack);

        // Read the XML document and perform validation
        while (validatingReader.Read())
        {
            // Process the XML nodes here
        }

        validatingReader.Close();
    }

    // Callback method for validation events
    private static void ValidationCallBack(object sender, ValidationEventArgs args)
    {
        if (args.Severity == XmlSeverityType.Warning)
        {
            Console.WriteLine($"Warning: {args.Message}");
        }
        else if (args.Severity == XmlSeverityType.Error)
        {
            Console.WriteLine($"Error: {args.Message}");
        }
    }
}

myDocument.xml:

<?xml version="1.0" encoding="utf-8"?>
<bookstore xmlns="http://www.contoso.com/books">
  <book category="COOKING">
    <title lang="en">Everyday Italian</title>
    <author>Giada De Laurentiis</author>
    <year>2005</year>
    <price>30.00</price>
  </book>
  <book category="CHILDREN">
    <title lang="en">Harry Potter</title>
    <author>J K. Rowling</author>
    <year>2005</year>
    <price>29.99</price>
  </book>
</bookstore>

mySchema.xsd:

<?xml version="1.0" encoding="utf-8"?>
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"
           targetNamespace="http://www.contoso.com/books"
           xmlns:book="http://www.contoso.com/books"
           elementFormDefault="qualified">

  <xs:element name="bookstore">
    <xs:complexType>
      <xs:sequence>
        <xs:element name="book" type="book:BookType" minOccurs="0" maxOccurs="unbounded" />
      </xs:sequence>
    </xs:complexType>
  </xs:element>

  <xs:complexType name="BookType">
    <xs:sequence>
      <xs:element name="title" type="xs:string" />
      <xs:element name="author" type="xs:string" />
      <xs:element name="year" type="xs:integer" />
      <xs:element name="price" type="xs:decimal" />
    </xs:sequence>
    <xs:attribute name="category" type="xs:string" use="required" />
  </xs:complexType>

</xs:schema>