Επεξεργασία

Κοινή χρήση μέσω


XmlValidatingReader.SchemaType Property

Definition

Gets a schema type object.

public:
 property System::Object ^ SchemaType { System::Object ^ get(); };
public object? SchemaType { get; }
public object SchemaType { get; }
member this.SchemaType : obj
Public ReadOnly Property SchemaType As Object

Property Value

XmlSchemaDatatype, XmlSchemaSimpleType, or XmlSchemaComplexType depending whether the node value is a built in XML Schema definition language (XSD) type or a user defined simpleType or complexType; null if the current node has no schema type.

Examples

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

#using <System.Xml.dll>
#using <System.dll>

using namespace System;
using namespace System::IO;
using namespace System::Xml;
using namespace System::Xml::Schema;

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

public:
   static void main()
   {
      XmlTextReader^ tr = gcnew XmlTextReader( "booksSchema.xml" );
      XmlValidatingReader^ vr = gcnew XmlValidatingReader( tr );
      vr->Schemas->Add( nullptr, "books.xsd" );
      vr->ValidationType = ValidationType::Schema;
      vr->ValidationEventHandler += gcnew ValidationEventHandler( Sample::ValidationCallBack );
      while ( vr->Read() )
      {
         if ( vr->NodeType == XmlNodeType::Element )
         {
            if ( dynamic_cast<XmlSchemaComplexType^>(vr->SchemaType) != nullptr )
            {
               XmlSchemaComplexType^ sct = dynamic_cast<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 );
            }
         }
      }
   }
};

int main()
{
   Sample::main();
}
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);
  }
}
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>

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.

The user needs to test for the returned type. For example,

object obj = vreader.SchemaType;  
 if (obj is XmlSchemaType)  
 {  
   XmlSchemaType st = (XmlSchemaType)obj;  
   // use XmlSchemaType object  
 }  
 if (obj is XmlSchemaDatatype)  
 {  
   XmlSchemaDatatype sd = (XmlSchemaDatatype)obj;  
   Type vt = sd.ValueType;  
   // use XmlSchemaDatatype object  
       }  

If XML Schema validation is being performed, the XmlSchemaType or XmlSchemaDatatype corresponds to the current element being read. If document type definition (DTD validation) is being performed, this property returns null.

XmlSchemaDatatype is returned if the current element, or attribute, is a simple type that can specify special validation constraints on the simple types, like min and max.

XmlSchemaSimpleType is returned if the current element, or attribute, is a user defined simpleType.

XmlSchemaComplexType is returned if the current element is a user defined complexType. This type cannot be returned by attributes.

Note

If ValidationType has been set to ValidationType.None, no data type information is provided from either schemas or DTDs.

Caution

After calling Close, SchemaType will return Null.

Applies to

See also