How to query default namespace with MSXML

Question

I have some XML:

Answer 1

Explicitly give the namespace a name when you add it to the SelectionNamespaces:

doc.setProperty("SelectionNamespaces",
      "xmlns:peanut='http://schemas.microsoft.com/developer/msbuild/2003'");

and then query using that namespace:

IDOMNode node = doc.selectSingleNode("//peanut:PropertyGroup/@Condition");

You can give that namespace any abbreviation name you want (peanut in this case). And then use the abbreviation as prefix (peanut:PropertyGroup in this case).

Earlier suggestions

I would try moving to Xml.Linq.

Here is a sample (with a namespace).

      try
    {

        XDocument xDoc1 = XDocument.Parse("<?xml version=\"1.0\" ?><Project ToolsVersion=\"4.0\" xmlns=\"http://schemas.microsoft.com/developer/msbuild/2003\"><PropertyGroup Condition=\"'$(key)'=='1111'\"><Key>Value</Key></PropertyGroup></Project>");
        XNamespace ns1 = XNamespace.Get("http://schemas.microsoft.com/developer/msbuild/2003");

        var list1 = from list in xDoc1.Descendants(ns1 + "Project")
                    from item in list.Elements(ns1 + "PropertyGroup")
                    /* where item.Element(ns + "HintPath") != null */
                    where item.Attribute("Condition") != null
                    select new
                    {
                        MyCondition = item.Attribute("Condition") == null ? "Not Here!" : item.Attribute("Condition").Value,
                        MyFake = item.Attribute("DoesNotExistTest") == null ? "Not Here Sucker!" : item.Attribute("DoesNotExistTest").Value
                    };


        foreach (var v in list1)
        {
            Console.WriteLine(v.ToString());
        }


        XDocument xDoc2 = XDocument.Parse("<?xml version=\"1.0\" encoding=\"UTF-16\" standalone=\"yes\"?>   <ShowPlanXML Version=\"1.1\" Build=\"10.50.1600.1\"                    xmlns=\"http://schemas.microsoft.com/sqlserver/2004/07/showplan\">      <BatchSequence>            <Batch>Something I Threw In Here</Batch>      </BatchSequence>    </ShowPlanXML> ");
        XNamespace ns2 = XNamespace.Get("http://schemas.microsoft.com/sqlserver/2004/07/showplan");

        var list2 = from list in xDoc2.Descendants(ns2 + "ShowPlanXML")
                    from item in list.Elements(ns2 + "BatchSequence")
                    /*                             where item.Attribute("Condition") != null */
                    where item.Element(ns2 + "Batch") != null 
                    select new
                    {
                        BatchValue = (item.Element(ns2 + "Batch") == null) ? string.Empty : item.Element(ns2 + "Batch").Value
                    };


        foreach (var v in list2)
        {
            Console.WriteLine(v.ToString());
        }



    }
    catch (Exception ex)
    {
        Console.WriteLine(ex.Message);
    }