XmlValidatingReader.ReadTypedValue Method ()

 
System_CAPS_noteNote

The .NET API Reference documentation has a new home. Visit the .NET API Browser on docs.microsoft.com to see the new experience.

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

Namespace:   System.Xml
Assembly:  System.Xml (in System.Xml.dll)

Public Function ReadTypedValue As Object

Return Value

Type: System.Object

The common language runtime type for the specified XML Schema type.

System_CAPS_noteNote

The XmlValidatingReader class is obsolete in .NET Framework 2.0.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.

For example, if the schema type is defined as xsd:int, the runtime type int32 is returned for the object. This can be tested using the GetType method and cast accordingly. The ReadTypedValue method always returns a type that is derived from the Object class. It never returns the Object type.

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.

System_CAPS_noteNote

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

System_CAPS_cautionCaution

After calling Close, ReadTypedValue will return null.

The following example displays the type information for each of the elements in the XML document.

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

The example uses the following input files.

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>

.NET Framework
Available since 1.1
Return to top
Show: