XmlValidatingReader.ReadTypedValue Method

.NET Framework Class Library

Gets the common language runtime type for the specified XML Schema definition language (XSD) type.

[Visual Basic]
Public Function ReadTypedValue() As Object
[C#]
public object ReadTypedValue();
[C++]
public: Object* ReadTypedValue();
[JScript]
public function ReadTypedValue() : Object;

Return Value

The common language runtime type for the specified XML Schema (XSD) type.

Remarks

For example, if the type is defined as xsd:int the the runtime type int32 is returned for the object. This can be tested using the GetType method and cast accordingly. This property always return a subclassed type of object. An object of the type object is never returned.If the reader is positioned on an attribute, this method returns the runtime typed object, but does not change the position of the reader. If the reader is positioned on an element, ReadTypedValue reads any CDATA, text, white space, significant white space, and comment nodes, returns the runtime typed object and positions the reader on the end tag. Any types that do not have a direct mapping, for example NMTOKENS, are returned as strings.

Note If ValidationType has been set to ValidationType.None, data type information is not provided from either schemas or DTDs.

CAUTION After calling Close, SchemaType will return Null.

Example

[Visual Basic, C#, C++] The following example displays the type information for each of the elements in the XML document.

[Visual Basic] 
Imports System
Imports System.IO
Imports System.Xml
Imports System.Xml.Schema

public class Sample

  public shared sub Main()
  
  Dim tr as XmlTextReader = new XmlTextReader("booksSchema.xml")
  Dim vr as XmlValidatingReader = new XmlValidatingReader(tr)
 
  vr.Schemas.Add(nothing, "books.xsd")
  vr.ValidationType = ValidationType.Schema
  AddHandler vr.ValidationEventHandler, AddressOf ValidationCallBack

  while(vr.Read())

    if(vr.NodeType = XmlNodeType.Element)
    
      if (vr.SchemaType.ToString() = "System.Xml.Schema.XmlSchemaComplexType")
        Dim sct as XmlSchemaComplexType = CType(vr.SchemaType,XmlSchemaComplexType)
        Console.WriteLine("{0}({1})", vr.Name, sct.Name)
      else      
        Dim value as object = vr.ReadTypedValue()
        Console.WriteLine("{0}({1}):{2}", vr.Name, value.GetType().Name, value)    
      end if
    end if
  end while
  end sub

  private shared sub ValidationCallBack (sender as object, args as ValidationEventArgs)

   Console.WriteLine("***Validation error")
   Console.WriteLine("Severity:{0}", args.Severity)
   Console.WriteLine("Message  :{0}", args.Message)
  end sub
end class

[C#] 
using System;
using System.IO;
using System.Xml;
using System.Xml.Schema;

public class Sample{

  public static void Main(){
  
  XmlTextReader tr = new XmlTextReader("booksSchema.xml");
  XmlValidatingReader vr = new XmlValidatingReader(tr);
 
  vr.Schemas.Add(null, "books.xsd");
  vr.ValidationType = ValidationType.Schema;
  vr.ValidationEventHandler += new ValidationEventHandler (ValidationCallBack);
 
  while(vr.Read()){
    if(vr.NodeType == XmlNodeType.Element){
      if(vr.SchemaType is XmlSchemaComplexType){
        XmlSchemaComplexType sct = (XmlSchemaComplexType)vr.SchemaType;
        Console.WriteLine("{0}({1})", vr.Name, sct.Name);
      }
      else{
        object value = vr.ReadTypedValue();
        Console.WriteLine("{0}({1}):{2}", vr.Name, value.GetType().Name, value);
      }
    }
  }
 }

  private static void ValidationCallBack (object sender, ValidationEventArgs args){
    Console.WriteLine("***Validation error");
    Console.WriteLine("\tSeverity:{0}", args.Severity);
    Console.WriteLine("\tMessage  :{0}", args.Message);
  }
}

[C++] 
#using <mscorlib.dll>
#using <System.Xml.dll>
using namespace System;
using namespace System::IO;
using namespace System::Xml;
using namespace System::Xml::Schema;

__gc public class Sample
{
public:
   static void ValidationCallBack (Object* sender, ValidationEventArgs * args)
   {
      Console::WriteLine(S"***Validation error");
      Console::WriteLine(S"\tSeverity: {0}", __box(args -> Severity));
      Console::WriteLine(S"\tMessage  : {0}", args -> Message);
   }
};

int main()
{
   XmlTextReader* tr = new XmlTextReader(S"booksSchema.xml");
   XmlValidatingReader* vr = new XmlValidatingReader(tr);

   vr -> Schemas->Add(0, S"books.xsd");
   vr -> ValidationType = ValidationType::Schema;
   vr -> ValidationEventHandler += new ValidationEventHandler (vr, Sample::ValidationCallBack);

   while (vr -> Read())
   {
      if (vr -> NodeType == XmlNodeType::Element) 
      {
         if (dynamic_cast<XmlSchemaComplexType*>(vr -> SchemaType) != 0)
         {
            XmlSchemaComplexType* sct = dynamic_cast<XmlSchemaComplexType*>( vr -> SchemaType );
            Console::WriteLine(S" {0}( {1})", vr -> Name, sct -> Name);
         } 
         else
         {
            Object* value = vr -> ReadTypedValue();
            Console::WriteLine(S" {0}( {1}): {2}", vr -> Name, value->GetType()->Name, value);
         }
      }
   }
}

[Visual Basic, C#, C++] The example uses the following input files.

[Visual Basic, C#, C++] booksSchema.xml

<?xml version='1.0'?>
<bookstore xmlns="urn:bookstore-schema">
  <book genre="autobiography">
    <title>The Autobiography of Benjamin Franklin</title>
    <author>
      <first-name>Benjamin</first-name>
      <last-name>Franklin</last-name>
    </author>
    <price>8.99</price>
  </book>
  <book genre="novel">
    <title>The Confidence Man</title>
    <author>
      <first-name>Herman</first-name>
      <last-name>Melville</last-name>
    </author>
    <price>11.99</price>
  </book>
</bookstore>

books.xsd

<xsd:schema xmlns:xsd="http://www.w3.org/2001/XMLSchema"
    xmlns="urn:bookstore-schema"
    elementFormDefault="qualified"
    targetNamespace="urn:bookstore-schema">

 <xsd:element name="bookstore" type="bookstoreType"/>

 <xsd:complexType name="bookstoreType">
  <xsd:sequence maxOccurs="unbounded">
   <xsd:element name="book"  type="bookType"/>
  </xsd:sequence>
 </xsd:complexType>

 <xsd:complexType name="bookType">
  <xsd:sequence>
   <xsd:element name="title" type="xsd:string"/>
   <xsd:element name="author" type="authorName"/>
   <xsd:element name="price"  type="xsd:decimal"/>
  </xsd:sequence>
  <xsd:attribute name="genre" type="xsd:string"/>
 </xsd:complexType>

 <xsd:complexType name="authorName">
  <xsd:sequence>
   <xsd:element name="first-name"  type="xsd:string"/>
   <xsd:element name="last-name" type="xsd:string"/>
  </xsd:sequence>
 </xsd:complexType>

</xsd:schema>

[JScript] No example is available for JScript. To view a Visual Basic, C#, or C++ example, click the Language Filter button in the upper-left corner of the page.

Requirements

Platforms: Windows 98, Windows NT 4.0, Windows Millennium Edition, Windows 2000, Windows XP Home Edition, Windows XP Professional, Windows Server 2003 family

Return Value

Remarks

Example

Requirements

See Also