XmlReader.ReadToDescendant Method (String)
Advances the XmlReader to the next descendant element with the specified qualified name.
Namespace: System.Xml
Assembly: System.Xml (in System.Xml.dll)
Parameters
- name
- Type: System.String
The qualified name of the element you wish to move to.
Return Value
Type: System.Booleantrue if a matching descendant element is found; otherwise false. If a matching child element is not found, the XmlReader is positioned on the end tag (NodeType is XmlNodeType.EndElement) of the element.
If the XmlReader is not positioned on an element when ReadToDescendant was called, this method returns false and the position of the XmlReader is not changed.
| Exception | Condition |
|---|---|
| InvalidOperationException | An XmlReader method was called before a previous asynchronous operation finished. In this case, InvalidOperationException is thrown with the message “An asynchronous operation is already in progress.” |
| ArgumentException | The parameter is an empty string. |
The following example parses the second book node.
using (XmlReader reader = XmlReader.Create("2books.xml")) { // Move the reader to the second book node. reader.MoveToContent(); reader.ReadToDescendant("book"); reader.Skip(); //Skip the first book. // Parse the file starting with the second book node. do { switch (reader.NodeType) { case XmlNodeType.Element: Console.Write("<{0}", reader.Name); while (reader.MoveToNextAttribute()) { Console.Write(" {0}='{1}'", reader.Name, reader.Value); } Console.Write(">"); break; case XmlNodeType.Text: Console.Write(reader.Value); break; case XmlNodeType.EndElement: Console.Write("</{0}>", reader.Name); break; } } while (reader.Read()); }
The example uses the file, 2books.xml, as input.
<!--sample XML fragment-->
<bookstore>
<book genre='novel' ISBN='10-861003-324'>
<title>The Handmaid's Tale</title>
<price>19.95</price>
</book>
<book genre='novel' ISBN='1-861001-57-5'>
<title>Pride And Prejudice</title>
<price>24.95</price>
</book>
</bookstore>
Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)
The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.
