How to put a Linq var in XDocument?

Question

I have the following code but it doesn't work. How can I make this work? The following code gives an exeption: newXdoc.Add(cComb); This operation would create an incorrectly structured document.

(Also thnx to Gert-Jan who provided the code for me partially)

private void button1_Click(object sender, EventArgs e)
{
    var x1 = XDocument.Load(sourceFilepathTb.Text);
    var x2 = XDocument.Load(targetFilepathTb.Text);

    // select the CLASS nodes from each
    var c1 = x1.Descendants("ActionDesign").First().Descendants("Action");
    var c2 = x2.Descendants("ActionDesign").First().Descendants("Action");

    // this one gives the distinct union of the two, you can 
    // put that into the result xdoc.
    var cComb =
        c1
        .Union(c2)
        .Distinct(new ClassComparer())
        .OrderBy(c => c.Attribute("Id").Value);

    XDocument newXdoc = new XDocument(
        new XDeclaration("1", "utf-8", null),
        new XElement("Application"));
    //newXdoc.Add(new XElement(cComb));
    //newXdoc.Add(new XDeclaration("1", "utf-8", "yes"));
    newXdoc.Add(cComb);

Answer 1

You're trying to add several elements to the absolute root of the document, giving several root elements.

The easiest way to fix this is just to use:

newXdoc.Root.Add(cComb);

That will add the elements to the existing root element instead.