XPathNavigator.ValueType Vlastnost

Definice

Obor názvů:

System.Xml.XPath

Sestavení:

System.Xml.ReaderWriter.dll

Zdroj:

XPathNavigator.cs

Získá .NET Type aktuálního uzlu.

public:
 virtual property Type ^ ValueType { Type ^ get(); };

public override Type ValueType { get; }

member this.ValueType : Type

Public Overrides ReadOnly Property ValueType As Type

Hodnota vlastnosti

Type

.NET Type aktuálního uzlu. Výchozí hodnota je String.

Příklady

V následujícím příkladu se k vytvoření XPathNavigator objektu contosoBooks.xml používá soubor XML a contosoBooks.xsd schéma jazyka XSD (XML Schema Definition Language). Zadaná hodnota elementu price se zobrazí pomocí ValueType vlastnosti a pak se vrátí jako řetězec pomocí ValueAs metody .

// Create an XmlReaderSettings object with the contosoBooks.xsd schema.
XmlReaderSettings^ settings = gcnew XmlReaderSettings();
settings->Schemas->Add("http://www.contoso.com/books", "contosoBooks.xsd");
settings->ValidationType = ValidationType::Schema;

// Create an XmlReader object with the contosoBooks.xml file and its schema.
XmlReader^ reader = XmlReader::Create("contosoBooks.xml", settings);

XPathDocument^ document = gcnew XPathDocument(reader);
XPathNavigator^ navigator = document->CreateNavigator();

navigator->MoveToChild("bookstore", "http://www.contoso.com/books");
navigator->MoveToChild("book", "http://www.contoso.com/books");
navigator->MoveToChild("price", "http://www.contoso.com/books");

// Display the current type of the price element.
Console::WriteLine(navigator->ValueType);

// Get the value of the price element as a string and display it.
String^ price = dynamic_cast<String^>(navigator->ValueAs(String::typeid));
Console::WriteLine(price);

// Create an XmlReaderSettings object with the contosoBooks.xsd schema.
XmlReaderSettings settings = new XmlReaderSettings();
settings.Schemas.Add("http://www.contoso.com/books", "contosoBooks.xsd");
settings.ValidationType = ValidationType.Schema;

// Create an XmlReader object with the contosoBooks.xml file and its schema.
XmlReader reader = XmlReader.Create("contosoBooks.xml", settings);

XPathDocument document = new XPathDocument(reader);
XPathNavigator navigator = document.CreateNavigator();

navigator.MoveToChild("bookstore", "http://www.contoso.com/books");
navigator.MoveToChild("book", "http://www.contoso.com/books");
navigator.MoveToChild("price", "http://www.contoso.com/books");

// Display the current type of the price element.
Console.WriteLine(navigator.ValueType);

// Get the value of the price element as a string and display it.
string price = navigator.ValueAs(typeof(string)) as string;
Console.WriteLine(price);

' Create an XmlReaderSettings object with the contosoBooks.xsd schema.
Dim settings As XmlReaderSettings = New XmlReaderSettings()
settings.Schemas.Add("http://www.contoso.com/books", "contosoBooks.xsd")
settings.ValidationType = ValidationType.Schema

' Create an XmlReader object with the contosoBooks.xml file and its schema.
Dim reader As XmlReader = XmlReader.Create("contosoBooks.xml", settings)

Dim document As XPathDocument = New XPathDocument(reader)
Dim navigator As XPathNavigator = document.CreateNavigator()

navigator.MoveToChild("bookstore", "http://www.contoso.com/books")
navigator.MoveToChild("book", "http://www.contoso.com/books")
navigator.MoveToChild("price", "http://www.contoso.com/books")

' Display the current type of the price element.
Console.WriteLine(navigator.ValueType)

' Get the value of the price element as a string and display it.
Dim price As String = navigator.ValueAs(GetType(String))
Console.WriteLine(price)

V příkladu se contosoBooks.xml soubor používá jako vstup.

<?xml version="1.0" encoding="utf-8" ?>  
<bookstore xmlns="http://www.contoso.com/books">  
    <book genre="autobiography" publicationdate="1981-03-22" ISBN="1-861003-11-0">  
        <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" publicationdate="1967-11-17" ISBN="0-201-63361-2">  
        <title>The Confidence Man</title>  
        <author>  
            <first-name>Herman</first-name>  
            <last-name>Melville</last-name>  
        </author>  
        <price>11.99</price>  
    </book>  
    <book genre="philosophy" publicationdate="1991-02-15" ISBN="1-861001-57-6">  
        <title>The Gorgias</title>  
        <author>  
            <name>Plato</name>  
        </author>  
        <price>9.99</price>  
    </book>  
</bookstore>  

V příkladu contosoBooks.xsd se jako vstup používá také hodnota .

<?xml version="1.0" encoding="utf-8"?>  
<xs:schema attributeFormDefault="unqualified" elementFormDefault="qualified" targetNamespace="http://www.contoso.com/books" xmlns:xs="http://www.w3.org/2001/XMLSchema">  
    <xs:element name="bookstore">  
        <xs:complexType>  
            <xs:sequence>  
                <xs:element maxOccurs="unbounded" name="book">  
                    <xs:complexType>  
                        <xs:sequence>  
                            <xs:element name="title" type="xs:string" />  
                            <xs:element name="author">  
                                <xs:complexType>  
                                    <xs:sequence>  
                                        <xs:element minOccurs="0" name="name" type="xs:string" />  
                                        <xs:element minOccurs="0" name="first-name" type="xs:string" />  
                                        <xs:element minOccurs="0" name="last-name" type="xs:string" />  
                                    </xs:sequence>  
                                </xs:complexType>  
                            </xs:element>  
                            <xs:element name="price" type="xs:decimal" />  
                        </xs:sequence>  
                        <xs:attribute name="genre" type="xs:string" use="required" />  
                        <xs:attribute name="publicationdate" type="xs:date" use="required" />  
                        <xs:attribute name="ISBN" type="xs:string" use="required" />  
                    </xs:complexType>  
                </xs:element>  
            </xs:sequence>  
        </xs:complexType>  
    </xs:element>  
</xs:schema>  

Poznámky

Vlastnost ValueType získá .NET Type zadané hodnoty aktuálního uzlu.

Například prvek typu xs:int by měl ve výchozím nastavení hodnotu z ValueTypeInt32 . Může však ValueType být libovolný z platných typů, které lze namapovat, xs:int například Int16 nebo Double.

Pokud uzel nemá žádný typ, je to ekvivalentem anotace typu na uzlu je xdt:untypedAtomic. V tomto případě ValueType vlastnost vrátí řetězec pro uzel. Další informace naleznete v tématu Podpora typů v System.Xml Třídy.