How to: Find All Nodes in a Namespace

You can filter on the namespace of each element or attribute to find all nodes in that particular namespace.

Example

The following example creates an XML tree with two namespaces. It then iterates through the tree and prints the names of all the elements and attributes in one of those namespaces.

string markup = @"<aw:Root xmlns:aw='https://www.adventure-works.com' xmlns:fc='www.fourthcoffee.com'>
  <fc:Child1>abc</fc:Child1>
  <fc:Child2>def</fc:Child2>
  <aw:Child3>ghi</aw:Child3>
  <fc:Child4>
    <fc:GrandChild1>jkl</fc:GrandChild1>
    <aw:GrandChild2>mno</aw:GrandChild2>
  </fc:Child4>
</aw:Root>";
XElement xmlTree = XElement.Parse(markup);
Console.WriteLine("Nodes in the https://www.adventure-works.com namespace");
IEnumerable<XElement> awElements =
    from el in xmlTree.Descendants()
    where el.Name.Namespace == "https://www.adventure-works.com"
    select el;
foreach (XElement el in awElements)
    Console.WriteLine(el.Name.ToString());
Imports <xmlns:aw="https://www.adventure-works.com">
Imports <xmlns:fc="www.fourthcoffee.com">

Module Module1
    Sub Main()
        Dim xmlTree As XElement = _
            <aw:Root>
                <fc:Child1>abc</fc:Child1>
                <fc:Child2>def</fc:Child2>
                <aw:Child3>ghi</aw:Child3>
                <fc:Child4>
                    <fc:GrandChild1>jkl</fc:GrandChild1>
                    <aw:GrandChild2>mno</aw:GrandChild2>
                </fc:Child4>
            </aw:Root>
        Console.WriteLine("Nodes in the https://www.adventure-works.com namespace")
        Dim awElements As IEnumerable(Of XElement) = _
            From el In xmlTree.Descendants() _
            Where (el.Name.Namespace = GetXmlNamespace(aw)) _
            Select el
        For Each el As XElement In awElements
            Console.WriteLine(el.Name.ToString())
        Next
    End Sub
End Module

This code produces the following output:

Nodes in the https://www.adventure-works.com namespace
{https://www.adventure-works.com}Child3
{https://www.adventure-works.com}GrandChild2

The XML file accessed by the following query contains purchase orders in two different namespaces. The query creates a new tree with just the elements in one of the namespaces.

This example uses the following XML document: Sample XML File: Consolidated Purchase Orders.

XDocument cpo = XDocument.Load("ConsolidatedPurchaseOrders.xml");
XNamespace aw = "https://www.adventure-works.com";
XElement newTree = new XElement("Root",
    from el in cpo.Root.Elements()
    where el.Name.Namespace == aw
    select el
);
Console.WriteLine(newTree);
Imports <xmlns:aw="https://www.adventure-works.com">

Module Module1
    Sub Main()
        Dim cpo As XDocument = XDocument.Load("ConsolidatedPurchaseOrders.xml")
        Dim newTree As XElement = _
            <Root>
                <%= From el In cpo.Root.Elements() _
                    Where el.Name.Namespace = GetXmlNamespace(aw) _
                    Select el %>
            </Root>
        Console.WriteLine(newTree)
    End Sub
End Module

This code produces the following output:

<Root>
  <aw:PurchaseOrder PONumber="11223" Date="2000-01-15" xmlns:aw="https://www.adventure-works.com">
    <aw:ShippingAddress>
      <aw:Name>Chris Preston</aw:Name>
      <aw:Street>123 Main St.</aw:Street>
      <aw:City>Seattle</aw:City>
      <aw:State>WA</aw:State>
      <aw:Zip>98113</aw:Zip>
      <aw:Country>USA</aw:Country>
    </aw:ShippingAddress>
    <aw:BillingAddress>
      <aw:Name>Chris Preston</aw:Name>
      <aw:Street>123 Main St.</aw:Street>
      <aw:City>Seattle</aw:City>
      <aw:State>WA</aw:State>
      <aw:Zip>98113</aw:Zip>
      <aw:Country>USA</aw:Country>
    </aw:BillingAddress>
    <aw:DeliveryInstructions>Ship only complete order.</aw:DeliveryInstructions>
    <aw:Item PartNum="LIT-01">
      <aw:ProductID>Litware Networking Card</aw:ProductID>
      <aw:Qty>1</aw:Qty>
      <aw:Price>20.99</aw:Price>
    </aw:Item>
    <aw:Item PartNum="LIT-25">
      <aw:ProductID>Litware 17in LCD Monitor</aw:ProductID>
      <aw:Qty>1</aw:Qty>
      <aw:Price>199.99</aw:Price>
    </aw:Item>
  </aw:PurchaseOrder>
</Root>

See Also

Concepts

Basic Queries (LINQ to XML)