XPathNavigator.PrependChildElement(String, String, String, String) Method

public:
 virtual void PrependChildElement(System::String ^ prefix, System::String ^ localName, System::String ^ namespaceURI, System::String ^ value);

public virtual void PrependChildElement (string prefix, string localName, string namespaceURI, string value);

public virtual void PrependChildElement (string? prefix, string localName, string? namespaceURI, string? value);

abstract member PrependChildElement : string * string * string * string -> unit
override this.PrependChildElement : string * string * string * string -> unit

Public Overridable Sub PrependChildElement (prefix As String, localName As String, namespaceURI As String, value As String)

Parameters

Exceptions

Examples

In the following example, a new pages child element is prepended to the beginning of the list of child elements of the first book element in the contosoBooks.xml file.

XmlDocument^ document = gcnew XmlDocument();
document->Load("contosoBooks.xml");
XPathNavigator^ navigator = document->CreateNavigator();

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

navigator->PrependChildElement(navigator->Prefix, "pages", navigator->LookupNamespace(navigator->Prefix), "100");

Console::WriteLine(navigator->OuterXml);

XmlDocument document = new XmlDocument();
document.Load("contosoBooks.xml");
XPathNavigator navigator = document.CreateNavigator();

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

navigator.PrependChildElement(navigator.Prefix, "pages", navigator.LookupNamespace(navigator.Prefix), "100");

Console.WriteLine(navigator.OuterXml);

Dim document As XmlDocument = New XmlDocument()
document.Load("contosoBooks.xml")
Dim navigator As XPathNavigator = document.CreateNavigator()

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

navigator.PrependChildElement(navigator.Prefix, "pages", navigator.LookupNamespace(navigator.Prefix), "100")

Console.WriteLine(navigator.OuterXml)

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

<?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

Prepending a child node adds the new node to the beginning of the list of child nodes for the current node. For example, when three child nodes exist for an element, the prepended node becomes the first child node. If no child nodes exist, then a new child node is created.

Namespace prefix and URI values can be obtained by using the LookupPrefix or LookupNamespace method. For example, the following syntax prepends a child element by using the in-scope namespace xmlns:bk="http://www.contoso.com/books":

navigator.PrependChildElement(navigator.Prefix, "pages", LookupNamespaceURI(navigator.Prefix), String.Empty)  

This creates the new child <bk:pages/> element.

The following are important notes to consider when using the PrependChildElement method.

• If the namespace prefix specified is null or String.Empty, then the prefix for the namespace URI of the new element is obtained from the current namespaces in-scope. If there is no namespace prefix assigned to the specified namespace URI at the current scope, then a namespace prefix is automatically generated.

• The PrependChildElement method is valid only when the XPathNavigator is positioned on an element node.

• The PrependChildElement method does not affect the position of the XPathNavigator.

Applies to