XmlValidatingReader.ValidationType Property

Reference

Definition

Namespace:: System.Xml

Assembly:: System.Xml.ReaderWriter.dll

Assembly:: System.Xml.dll

Assembly:: netstandard.dll

Source:: XmlValidatingReader.cs

Source:: XmlValidatingReader.cs

Source:: XmlValidatingReader.cs

Important

Some information relates to prerelease product that may be substantially modified before it’s released. Microsoft makes no warranties, express or implied, with respect to the information provided here.

Gets or sets a value indicating the type of validation to perform.

public:
 property System::Xml::ValidationType ValidationType { System::Xml::ValidationType get(); void set(System::Xml::ValidationType value); };

public System.Xml.ValidationType ValidationType { get; set; }

member this.ValidationType : System.Xml.ValidationType with get, set

Public Property ValidationType As ValidationType

Property Value

ValidationType

One of the ValidationType values. If this property is not set, it defaults to ValidationType.Auto.

Exceptions

InvalidOperationException

Setting the property after a Read has been called.

Examples

The following example validates two files.

#using <System.Xml.dll>

using namespace System;
using namespace System::IO;
using namespace System::Xml;
using namespace System::Xml::Schema;
public ref class Sample
{
private:
   XmlTextReader^ txtreader;
   XmlValidatingReader^ reader;
   Boolean m_success;

public:
   Sample()
   {
      txtreader = nullptr;
      reader = nullptr;
      m_success = true;
      String^ doc1 = "notValid.xml";
      String^ doc2 = "cdDTD.xml";
      String^ doc3 = "book1.xml";
      
      //Parse the files and validate when requested.
      Validate( doc1, ValidationType::XDR ); //Validation should fail.
      Validate( doc2, ValidationType::DTD ); //Validation should fail.
      Validate( doc3, ValidationType::None ); //No validation performed.
   }


private:
   void Validate( String^ filename, ValidationType vt )
   {
      try
      {
         
         //Implement the readers.  Set the ValidationType.
         txtreader = gcnew XmlTextReader( filename );
         reader = gcnew XmlValidatingReader( txtreader );
         reader->ValidationType = vt;
         
         //If the reader is set to validate, set the event handler.
         if ( vt == ValidationType::None )
                  Console::WriteLine( "\nParsing XML file {0}", filename );
         else
         {
            Console::WriteLine( "\nValidating XML file {0}", filename );
            m_success = true;
            
            //Set the validation event handler.
            reader->ValidationEventHandler += gcnew ValidationEventHandler( this, &Sample::ValidationCallBack );
         }
         
         // Read XML data
         while ( reader->Read() )
         {}
         if ( vt == ValidationType::None )
                  Console::WriteLine( "Finished parsing file." );
         else
                  Console::WriteLine( "Validation finished. Validation {0}", m_success ? (String^)"successful" : "failed" );
      }
      finally
      {
         
         //Close the reader.
         if ( reader != nullptr )
                  reader->Close();
      }

   }


   //Display the validation errors.
   void ValidationCallBack( Object^ /*sender*/, ValidationEventArgs^ args )
   {
      m_success = false;
      Console::Write( "\r\n\tValidation error: {0}", args->Message );
   }

};

int main()
{
   gcnew Sample;
}

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

public class Sample
{
  private const String doc1 = "notValid.xml";
  private const String doc2 = "cdDTD.xml";
  private const String doc3 = "book1.xml";

  private XmlTextReader txtreader = null;
  private XmlValidatingReader reader = null;
  private Boolean m_success = true;

  public Sample ()
  {
      //Parse the files and validate when requested.
      Validate(doc1, ValidationType.XDR);  //Validation should fail.
      Validate(doc2, ValidationType.DTD);  //Validation should fail.
      Validate(doc3, ValidationType.None); //No validation performed.
  }

  public static void Main ()
  {
      Sample validation = new Sample();
  }

  private void Validate(String filename, ValidationType vt)
  {
    try
    {
        //Implement the readers.  Set the ValidationType.
        txtreader = new XmlTextReader(filename);
        reader = new XmlValidatingReader(txtreader);
        reader.ValidationType = vt;

        //If the reader is set to validate, set the event handler.
        if (vt==ValidationType.None)
            {
                Console.WriteLine("\nParsing XML file " + filename.ToString());
            }
            else
            {
           Console.WriteLine("\nValidating XML file " + filename.ToString());
           m_success = true;
           //Set the validation event handler.
           reader.ValidationEventHandler += new ValidationEventHandler (ValidationCallBack);
        }

        // Read XML data
        while (reader.Read()){}

        if (vt==ValidationType.None)
           Console.WriteLine("Finished parsing file.");
        else
          Console.WriteLine ("Validation finished. Validation {0}", (m_success==true ? "successful" : "failed"));
     }

     finally
     {
        //Close the reader.
        if (reader != null)
          reader.Close();
     }
  }

  //Display the validation errors.
  private void ValidationCallBack (object sender, ValidationEventArgs args)
  {
     m_success = false;

     Console.Write("\r\n\tValidation error: " + args.Message);
  }
}

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

Public Class Sample
    Private doc1 As String = "notValid.xml"
    Private doc2 As String = "cdDTD.xml"
    Private doc3 As String = "book1.xml"
    
    Private txtreader As XmlTextReader = Nothing
    Private reader As XmlValidatingReader = Nothing
    Private m_success As Boolean = True
    
    Public Sub New()
        'Parse the files and validate when requested.
        Validate(doc1, ValidationType.XDR) 'Validation should fail.
        Validate(doc2, ValidationType.DTD) 'Validation should fail.
        Validate(doc3, ValidationType.None) 'No validation performed.
    End Sub
    
    Public Shared Sub Main()
        Dim validation As New Sample()
    End Sub
    
    Private Sub Validate(filename As String, vt As ValidationType)
        Try
            'Implement the readers.  Set the ValidationType.
            txtreader = New XmlTextReader(filename)
            reader = New XmlValidatingReader(txtreader)
            reader.ValidationType = vt
            
            'If the reader is set to validate, set the event handler.
            If vt = ValidationType.None Then
                Console.WriteLine(ControlChars.Cr & "Parsing XML file " & filename.ToString())
            Else
                Console.WriteLine(ControlChars.Cr & "Validating XML file " & filename.ToString())
                m_success = True
                'Set the validation event handler.
                AddHandler reader.ValidationEventHandler, AddressOf ValidationCallBack
            End If
            
            ' Read XML data
            While reader.Read()
            End While 
            If vt = ValidationType.None Then
                Console.WriteLine("Finished parsing file.")
            Else
                Console.WriteLine("Validation finished. Validation {0}", IIf(m_success, "successful", "failed"))
            End If
        
        Finally
            'Close the reader.
            If Not (reader Is Nothing) Then
                reader.Close()
            End If
        End Try 
    End Sub
    
    'Display the validation errors.
    Private Sub ValidationCallBack(sender As Object, args As ValidationEventArgs)
        m_success = False
        
        Console.Write(ControlChars.CrLf & ControlChars.Tab & "Validation error: " & args.Message)
    End Sub
End Class

The sample uses the following four input files:

notValid.xml (The "x-schema:" prefix identifies the XML-Data Reduced (XDR) schema for the reader.)


<?xml version='1.0'?>
<bookstore xmlns="x-schema:schema1.xdr">
  <book genre="novel" style="hardcover">
    <title>The Handmaid's Tale</title>
    <author>
      <first-name>Margaret</first-name>
      <last-name>Atwood</last-name>
    </author>
    <price>19.95</price>
  </book>
  <book genre="novel" style="other">
    <title>The Poisonwood Bible</title>
    <author>
      <first-name>Barbara</first-name>
      <last-name>Kingsolver</last-name>
    </author>
    <price>11.99</price>
  </book>
</bookstore>

schema1.xdr


<?xml version="1.0"?>
 <Schema xmlns="urn:schemas-microsoft-com:xml-data"
         xmlns:dt="urn:schemas-microsoft-com:datatypes">
   <ElementType name="first-name" content="textOnly"/>
   <ElementType name="last-name" content="textOnly"/>
   <ElementType name="name" content="textOnly"/>
   <ElementType name="price" content="textOnly" dt:type="fixed.14.4"/>
   <ElementType name="author" content="eltOnly" order="one">
     <group order="seq">
       <element type="name"/>
     </group>
     <group order="seq">
       <element type="first-name"/>
       <element type="last-name"/>
     </group>
   </ElementType>
   <ElementType name="title" content="textOnly"/>
   <AttributeType name="genre" dt:type="string"/>
   <AttributeType name="style" dt:type="enumeration"
         dt:values="paperback hardcover"/>
   <ElementType name="book" content="eltOnly">
     <attribute type="genre" required="yes"/>
     <attribute type="style" required="yes"/>
     <element type="title"/>
     <element type="author"/>
     <element type="price"/>
   </ElementType>
   <ElementType name="bookstore" content="eltOnly">
     <element type="book"/>
   </ElementType>
 </Schema>

cdDTD.xml


<!--XML file using a DTD-->
<!DOCTYPE bookstore [
  <!ELEMENT bookstore (cd)*> 
  <!ELEMENT cd (title,artist,price)>
  <!ATTLIST cd genre CDATA #REQUIRED>
  <!ELEMENT title (#PCDATA)>
  <!ELEMENT artist (#PCDATA)>
  <!ELEMENT price (#PCDATA)>]>
<bookstore>
  <cd genre="alternative"  ISBN="2-3631-4">
    <title>Americana</title>
    <artist>Offspring</artist>
    <price>16.95</price>
  </cd>
</bookstore>

book1.xml


<?xml version='1.0' ?>
<!DOCTYPE book [<!ENTITY h 'hardcover'>]>
<book>
  <title>Pride And Prejudice</title>
  <misc>&h;</misc>
</book>

Remarks

Note

The XmlValidatingReader class is obsolete in .NET Framework 2.0. You can create a validating XmlReader instance by using the XmlReaderSettings class and the Create method. For more information, see the Remarks section of the XmlReader reference page.

This property must be set before the first call to Read. Setting this property to ValidationType.None creates a non-validating reader.

If external document type definitions (DTDs) or schemas are needed for validation, the XmlResolver is used.

Applies to

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