Question

Please have a look at the XML file. I would like to sort the XML file by <Order> tag

<MyRootNode>
  <Tab>
    <Name>ABC</Name>
    <Order>200</Order>
  </Tab>
  <Tab>
    <Name>MNO</Name>
    <Order>100</Order>
  </Tab>
  <Tab>
    <Name>XYZ</Name>
    <Order>90</Order>
  </Tab>
  <Tab>
    <Name>QWE</Name>
    <Order>40</Order>
  </Tab>
  <Tab>
    <Name>KML</Name>
    <Order>20</Order>
  </Tab>
</MyRootNode>

So the answer will be the following.

<MyRootNode>
  <Tab>
    <Name>KML</Name>
    <Order>20</Order>
  </Tab>
  <Tab>
    <Name>QWE</Name>
    <Order>40</Order>
  </Tab>
  <Tab>
    <Name>XYZ</Name>
    <Order>90</Order>
  </Tab>
  <Tab>
    <Name>MNO</Name>
    <Order>100</Order>
  </Tab>
  <Tab>
    <Name>ABC</Name>
    <Order>200</Order>
  </Tab>
</MyRootNode>

How can I do it in C# 3.5 ?

Answer 1

Have you tried,

XElement root = XElement.Load(xmlfile);
var orderedtabs = root.Elements("Tab")
                      .OrderBy(xtab => (int)xtab.Element("Order"))
                      .ToArray();
root.RemoveAll();
foreach(XElement tab in orderedtabs)
    root.Add(tab);
root.Save(xmlfile);