How to: Find Descendants with a Specific Element Name
Sometimes you want to find all descendants with a particular name. You could write code to iterate through all of the descendants, but it is easier to use the Descendants axis.
Example
The following example shows how to find descendants based on the element name.
XElement root = XElement.Parse(@"<root>
<para>
<r>
<t>Some text </t>
</r>
<n>
<r>
<t>that is broken up into </t>
</r>
</n>
<n>
<r>
<t>multiple segments.</t>
</r>
</n>
</para>
</root>");
IEnumerable<string> textSegs =
from seg in root.Descendants("t")
select (string)seg;
string str = textSegs.Aggregate(new StringBuilder(),
(sb, i) => sb.Append(i),
sp => sp.ToString()
);
Console.WriteLine(str);
Dim root As XElement = _
<root>
<para>
<r>
<t>Some text </t>
</r>
<n>
<r>
<t>that is broken up into </t>
</r>
</n>
<n>
<r>
<t>multiple segments.</t>
</r>
</n>
</para>
</root>
Dim textSegs As IEnumerable(Of String) = _
From seg In root...<t> _
Select seg.Value
Dim str As String = textSegs.Aggregate( _
New StringBuilder, _
Function(sb, i) sb.Append(i), _
Function(sb) sb.ToString)
Console.WriteLine(str)
This code produces the following output:
Some text that is broken up into multiple segments.
The following example shows the same query for XML that is in a namespace. For more information, see Working with XML Namespaces.
XElement root = XElement.Parse(@"<root xmlns='http://www.adatum.com'>
<para>
<r>
<t>Some text </t>
</r>
<n>
<r>
<t>that is broken up into </t>
</r>
</n>
<n>
<r>
<t>multiple segments.</t>
</r>
</n>
</para>
</root>");
XNamespace ad = "http://www.adatum.com";
IEnumerable<string> textSegs =
from seg in root.Descendants(ad + "t")
select (string)seg;
string str = textSegs.Aggregate(new StringBuilder(),
(sb, i) => sb.Append(i),
sp => sp.ToString()
);
Console.WriteLine(str);
Imports <xmlns='http://www.adatum.com'>
Module Module1
Sub Main()
Dim root As XElement = _
<root>
<para>
<r>
<t>Some text </t>
</r>
<n>
<r>
<t>that is broken up into </t>
</r>
</n>
<n>
<r>
<t>multiple segments.</t>
</r>
</n>
</para>
</root>
Dim textSegs As IEnumerable(Of String) = _
From seg In root...<t> _
Select seg.Value
Dim str As String = textSegs.Aggregate( _
New StringBuilder, _
Function(sb, i) sb.Append(i), _
Function(sb) sb.ToString)
Console.WriteLine(str)
End Sub
End Module
This code produces the following output:
Some text that is broken up into multiple segments.