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XmlValidatingReader.ReadTypedValue Method

Definition

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

C#
public object? ReadTypedValue();
C#
public object ReadTypedValue();

Returns

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

Examples

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

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);
  }
}

The example uses the following input files.

booksSchema.xml

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

XML
<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>

Remarks

Бележка

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.

Бележка

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

Внимание

After calling Close, ReadTypedValue will return null.

Applies to

Продукт Версии
.NET Core 2.0, Core 2.1, Core 2.2, Core 3.0, Core 3.1, 5, 6, 7, 8, 9, 10
.NET Framework 1.1, 2.0, 3.0, 3.5, 4.0, 4.5, 4.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8, 4.8.1
.NET Standard 2.0, 2.1

See also