asked on

Reading xml node value from xpath usning c#, xml have many different namespaces

Hi,

I am working in Asp.net 2.0 using C# and reading xml from xpath query

I need to read Key and value inner text from my attached xml file

All key and Value node is at xpath in given xml file:

\\tcm:Component\tcm:Data\tcm:Content\Resources\Text

I am getting null values from my below code

// node.SelectSingleNode("Key", ns) this value is null
// node.SelectSingleNode("Key") is also coming null

therefore unable to read inner text, may be because of lot of namespaces.

Can you please help in this

Many Thanks ComponentTest.xml

private void getComponentResourceKeyValue(string xml)
        {
            try
            {
                XmlDocument doc = new XmlDocument();
                doc.LoadXml(xml);

                XmlNamespaceManager ns = new XmlNamespaceManager(doc.NameTable);
                ns.AddNamespace("tcm", "http://www.tridion.com/ContentManager/5.0");
                ns.AddNamespace("xlink", "http://www.w3.org/1999/xlink");
                ns.AddNamespace(string.Empty, "http://www.testcomp.com/tridion/schemas");

                XmlNodeList nodeList = doc.SelectNodes("//*[local-name()='Text']"); // This is giving me nodelist with no issues

                foreach (XmlNode node in nodeList)
                {
 			// node.SelectSingleNode("Key", ns) this value is null
			// node.SelectSingleNode("Key") is also coming null


                    string key = node.SelectSingleNode("Key", ns).InnerText;
                    string value = node.SelectSingleNode("Value", ns).InnerText;

                }
            }
            catch (Exception ex)
            {
                throw ex;
            }           
        }

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ASKER CERTIFIED SOLUTION

nmarun

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SOLUTION

Dmitry G

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Dmitry G

About nmarun's solution.

I was thinking about it. But usually there is no guarantee in elements order...

So, if not guarantee - don't use...

nmarun

anarki_jimbel, seems like you were doing some vb.net before, your post has C# and vb.net code mixed up. The piece of code that'll work is:

ele.GetElementsByTagName("Key").Item[0].InnerText;

You are right about the order, so here's a fix for that.

foreach (XmlNode node in nodeList)
{
    string key = string.Empty;
    string value = string.Empty;
    for (int i = 0; i < node.ChildNodes.Count; i++)
    {
        switch (node.ChildNodes[i].Name)
        {
            case "Key":
                key = node.ChildNodes[i].InnerText;
                break;
            case "Value":
                value = node.ChildNodes[i].InnerText;
                break;
        }
    }

    Console.WriteLine("{0} - {1}", key, value);
}

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nmarun

And as a last step, I found the correct xpath for the code that the author was trying.

XmlNodeList nodeList = doc.SelectNodes("//*[local-name()='Text']"); 
foreach (XmlNode node in nodeList)
{
    var key = node.SelectSingleNode("*[local-name()='Key']").InnerText;
    var value = node.SelectSingleNode("*[local-name()='Value']").InnerText;
    Console.WriteLine("{0} - {1}", key, value);
}

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Sathish DV

Hi,

Its good it follow the solution given by mmarun. But if you still need more specifically from Namespacemanager(XmlDocument object is agnostic to Namespaces. It believes Namespaces exist hence why XmlNode has a Namespace property but the XPath parsers do not by default know what namespaces are at play in the document) you can better follow this one.

Replace the below code

                    string key = node.SelectSingleNode("Key", ns).InnerText;
                    string value = node.SelectSingleNode("Value", ns).InnerText;

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with

                    string key = node.SelectSingleNode("//*[local-name()='Key']", ns).InnerText;
                    string value = node.SelectSingleNode("//*[local-name()='Value']", ns).InnerText;

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nmarun

sathishinfotech, The '//' is incorrect. It's basically telling the xpath to look from the root node every time and not from the current selected Text node. This will result in the InnerText of the first Key and Value nodes everytime.

Arun

Dmitry G

nmarun, try to run my code - no errors there. I use methods, not indexed properties!

Usually I post ONLY code I can run...

Dmitry G

About XmlNodeList.Item METHOD:

http://msdn.microsoft.com/en-us/library/system.xml.xmlnodelist.item(v=VS.80).aspx

As a matter of fact, I can program freely in both C# and VB.

nmarun

anarki_jimbel, My bad, your code does work.

Dmitry G

Sorry, today's Monday - I'm grumpy... :)