XPathNodeIterator.Current Property

Reference

Definition

Namespace:: System.Xml.XPath

Assemblies:: netstandard.dll, System.Xml.ReaderWriter.dll

Assembly:: System.Xml.XPath.dll

Assembly:: System.Xml.ReaderWriter.dll

Assembly:: System.Xml.dll

Assembly:: netstandard.dll

Source:: XPathNodeIterator.cs

Source:: XPathNodeIterator.cs

Source:: XPathNodeIterator.cs

Important

Some information relates to prerelease product that may be substantially modified before it’s released. Microsoft makes no warranties, express or implied, with respect to the information provided here.

When overridden in a derived class, gets the XPathNavigator object for this XPathNodeIterator, positioned on the current context node.

public:
 abstract property System::Xml::XPath::XPathNavigator ^ Current { System::Xml::XPath::XPathNavigator ^ get(); };

public abstract System.Xml.XPath.XPathNavigator? Current { get; }

public abstract System.Xml.XPath.XPathNavigator Current { get; }

member this.Current : System.Xml.XPath.XPathNavigator

Public MustOverride ReadOnly Property Current As XPathNavigator

Property Value

XPathNavigator

An XPathNavigator object positioned on the context node from which the node set was selected. The MoveNext() method must be called to move the XPathNodeIterator to the first node in the selected set.

Examples

The following example gets all book titles authored by Herman Melville using the Current property of the XPathNodeIterator object and the Clone method of the XPathNavigator class.

XPathDocument^ document = gcnew XPathDocument("books.xml");
XPathNavigator^ navigator = document->CreateNavigator();

// Select all books authored by Melville.
XPathNodeIterator^ nodes = navigator->Select("descendant::book[author/last-name='Melville']");

while (nodes->MoveNext())
{
    // Clone the navigator returned by the Current property. 
    // Use the cloned navigator to get the title element.
    XPathNavigator^ clone = nodes->Current->Clone();
    clone->MoveToFirstChild();
    Console::WriteLine("Book title: {0}", clone->Value);
}

XPathDocument document = new XPathDocument("books.xml");
XPathNavigator navigator = document.CreateNavigator();

// Select all books authored by Melville.
XPathNodeIterator nodes = navigator.Select("descendant::book[author/last-name='Melville']");

while (nodes.MoveNext())
{
    // Clone the navigator returned by the Current property.
    // Use the cloned navigator to get the title element.
    XPathNavigator clone = nodes.Current.Clone();
    clone.MoveToFirstChild();
    Console.WriteLine("Book title: {0}", clone.Value);
}

Dim document As XPathDocument = New XPathDocument("books.xml")
Dim navigator As XPathNavigator = document.CreateNavigator()

' Select all books authored by Melville.
Dim nodes As XPathNodeIterator = navigator.Select("descendant::book[author/last-name='Melville']")

While nodes.MoveNext()
    ' Clone the navigator returned by the Current property. 
    ' Use the cloned navigator to get the title element.
    Dim clone As XPathNavigator = nodes.Current.Clone()
    clone.MoveToFirstChild()
    Console.WriteLine("Book title: {0}", clone.Value)
End While

The example takes the contosoBooks.xml file as input.

XML

<?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>

Remarks

You can use the properties of the returned XPathNavigator object to obtain information on the current node. However, the returned XPathNavigator object should not be modified. The returned XPathNavigator object cannot be moved away from the selected node set.

Alternatively, you can clone the XPathNavigator object using the Clone method of the XPathNavigator class. The cloned XPathNavigator object can then be moved away from the selected node set. This method of cloning the XPathNavigator object might affect the performance of the XPath query.

If the SelectAncestors, SelectDescendants, and SelectChildren methods result in no nodes being selected, the Current property might not be pointing to the context node.

To test whether nodes have been selected, use the Count property as shown in the following example.

Applies to

Продукт	Версии
.NET	Core 1.0, Core 1.1, 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

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