Question

Please check my code –
XML-

 <LocalXML>
  <PnrDetails SearchType="Outbound">
    <GDSPNR></GDSPNR>
  </PnrDetails>
  <PnrDetails SearchType="Inbound">
    <GDSPNR></GDSPNR>
  </PnrDetails>
</LocalXML>

Code –

XDocument doc = XDocument.Load(@"RSP.xml");
            var ele = doc.Root.Elements("PnrDetails");
            foreach (XElement e in ele)
            {
                if (e.Element("GDSPNR").Value.Equals(""))
                {
                    e.Elements().Remove();
                    e.Add(new XElement("ErrorMessage", "Booking is not confirmed")
                    );
                }
            }

My code is working fine.Now my question is that can I use Lambda Expression in above code to check whether GDSPNR value null or not.If yes then please tell me how?

Thanks in advance.

EDIT XML –

<LocalXML>
  <PnrDetails SearchType="Outbound">
    <GDSPNR></GDSPNR>
    <SPNR>abc</SPNR>
    <DSPNR>xyz</DSPNR>
  </PnrDetails>
  <PnrDetails SearchType="Inbound">
    <GDSPNR></GDSPNR>
    <SPNR>abx</SPNR>
    <DSPNR>cds</DSPNR>
  </PnrDetails>
</LocalXML>

Answer 1

How about this (based entirely on what your current logic is doing):

    IEnumerable<XElement> nodesToBeReplaced = document.Root
        .Elements("PnrDetails")
        .Descendants("GDSPNR")
        .Where(element => element.Value.Equals(string.Empty));

    foreach (XElement element in nodesToBeReplaced)
    {
        element.Name = "ErrorMessage";
        element.Value = "Booking is not confirmed";
    }

If instead you mean, PnrDetails without a child tag of GDSPNR, like this:

  <PnrDetails SearchType=""Outbound"">
  </PnrDetails>

Then you can do the following:

    IEnumerable<XElement> nodesWithMissingChildElements = document.Root
        .Elements("PnrDetails")
        .Where(element => !element.Descendants("GDSPNR").Any());