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XPathNavigator.MoveToFirstAttribute Method

  • Reference

Definition

Namespace:
System.Xml.XPath
Assembly:
System.Xml.ReaderWriter.dll
Assembly:
System.Xml.XPath.dll
Assembly:
System.Xml.dll
Assembly:
netstandard.dll
Source:
XPathNavigator.cs
Source:
XPathNavigator.cs
Source:
XPathNavigator.cs

When overridden in a derived class, moves the XPathNavigator to the first attribute of the current node.

public:
 abstract bool MoveToFirstAttribute();
public abstract bool MoveToFirstAttribute ();
abstract member MoveToFirstAttribute : unit -> bool
Public MustOverride Function MoveToFirstAttribute () As Boolean

Returns

Boolean

true if the XPathNavigator is successful moving to the first attribute of the current node; otherwise, false. If false, the position of the XPathNavigator is unchanged.

Examples

The following example uses the MoveToFirstAttribute and MoveToNextAttribute methods to display all the attributes for each book in the books.xml file.

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

  // Select all book nodes and display all attributes on each book.
  XPathNodeIterator^ nodes = navigator->SelectDescendants("book", "", false);
  while (nodes->MoveNext())
  {
      XPathNavigator^ navigator2 = nodes->Current->Clone();
      navigator2->MoveToFirstAttribute();
      Console::WriteLine("{0} = {1}", navigator2->Name, navigator2->Value);

      while (navigator2->MoveToNextAttribute())
      {
          Console::WriteLine("{0} = {1}", navigator2->Name, navigator2->Value);
      }

      Console::WriteLine();
  }

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

// Select all book nodes and display all attributes on each book.
XPathNodeIterator nodes = navigator.SelectDescendants("book", "", false);
while (nodes.MoveNext())
{
    XPathNavigator navigator2 = nodes.Current.Clone();
    navigator2.MoveToFirstAttribute();
    Console.WriteLine("{0} = {1}", navigator2.Name, navigator2.Value);

    while (navigator2.MoveToNextAttribute())
    {
        Console.WriteLine("{0} = {1}", navigator2.Name, navigator2.Value);
    }

    Console.WriteLine();
}

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

' Select all book nodes and display all attributes on each book.
Dim nodes As XPathNodeIterator = navigator.SelectDescendants("book", "", False)
While nodes.MoveNext()
    Dim navigator2 As XPathNavigator = nodes.Current.Clone()
    navigator2.MoveToFirstAttribute()
    Console.WriteLine("{0} = {1}", navigator2.Name, navigator2.Value)

    While navigator2.MoveToNextAttribute()
        Console.WriteLine("{0} = {1}", navigator2.Name, navigator2.Value)
    End While

    Console.WriteLine()
End While

The example takes the books.xml file as an input.

<?xml version="1.0" encoding="utf-8" ?>   
<bookstore>  
    <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

If the XPathNavigator is not currently positioned on an element, this method returns false and the position of the XPathNavigator does not change.

After a successful call to MoveToFirstAttribute, the LocalName, NamespaceURI and Prefix properties reflect the values of the attribute. When the XPathNavigator is positioned on an attribute, the methods MoveToNext, MoveToPrevious, and MoveToFirst are not applicable. These methods always return false and do not change the position of the XPathNavigator. Rather, you can call MoveToNextAttribute to move to the next attribute node.

After the XPathNavigator is positioned on an attribute, you can call MoveToParent to move to the owner element.

Applies to

See also