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How to sort elements (LINQ to XML)

  • บทความ

You can sort your results when you query XML. This article provides two examples: the first sorts results for XML that isn't in a namespace, and the second does the same sort, but for XML that is in a namespace.

Example: Write a query that sorts its results

This example shows how to write a query that sorts its results. It uses XML document Sample XML file: Numerical data.

XElement root = XElement.Load("Data.xml");
IEnumerable<decimal> prices =
    from el in root.Elements("Data")
    let price = (decimal)el.Element("Price")
    orderby price
    select price;
foreach (decimal el in prices)
    Console.WriteLine(el);

Dim root As XElement = XElement.Load("Data.xml")
Dim prices As IEnumerable(Of Decimal) = _
    From el In root.<Data> _
    Let price = Convert.ToDecimal(el.<Price>.Value) _
    Order By (price) _
    Select price
For Each el As Decimal In prices
    Console.WriteLine(el)
Next

This example produces the following output:

0.99
4.95
6.99
24.50
29.00
66.00
89.99

Example: Write a query in a namespace that sorts its results

The following example shows the same query for XML that's in a namespace. It uses XML document Sample XML file: Numerical data in a namespace.

For more information, see Namespaces overview.

XElement root = XElement.Load("DataInNamespace.xml");
XNamespace aw = "http://www.adatum.com";
IEnumerable<decimal> prices =
    from el in root.Elements(aw + "Data")
    let price = (decimal)el.Element(aw + "Price")
    orderby price
    select price;
foreach (decimal el in prices)
    Console.WriteLine(el);

Imports <xmlns='http://www.adatum.com'>

Module Module1
    Sub Main()
        Dim root As XElement = XElement.Load("DataInNamespace.xml")
        Dim prices As IEnumerable(Of Decimal) = _
            From el In root.<Data> _
            Let price = Convert.ToDecimal(el.<Price>.Value) _
            Order By (price) _
            Select price
        For Each el As Decimal In prices
            Console.WriteLine(el)
        Next
    End Sub
End Module

This example produces the following output:

0.99
4.95
6.99
24.50
29.00
66.00
89.99

See also