Problem with updating values to .xml file

Question

Hello,

Im trying to update(measurement values from serial port) data from array to .xml file. The .xml file consists of sensor nodes which have child nodes: value, description and id. Only value nodes needs to be updated.

The code I have "achieved" so far only works if there is only one <sensorX> node, and I can't figure how could I get it to update each <value> node in the file. I believe this shouldn't be too difficult, maybe I'm just missing something...

The code... looks like this at the moment, please comment...

private void xmlWrite()
        {
            System.Xml.XmlDocument xmldoc = new
            System.Xml.XmlDocument();
            int id = 0;               
            xmldoc.Load("C:\\data2.xml");           
            System.Xml.XmlNode nood = xmldoc.SelectSingleNode("sensor");
            foreach (System.Xml.XmlNode node in nood)
                {
                    if (node.Name == "value")
                    {
                        node.InnerXml = arData[id];
                        id++;
                    }
                }
            xmldoc.Save("E:\\test3.xml");
         }

I tried to add foreach-loop before the "System.Xml.XmlNode" and +id after "sensor", but it only gave always some "null reference error"...

 

The .xml file looks like this(form of the content can also be changed if eases the saving procedure):

<sensor0>
    <id>T10</id>
    <description>Temperature0</description>
    <value>0</value>
</sensor0>
<sensor1>
    <id>T11</id>
    <description>Temperature1</description>
    <value>0</value>
</sensor1>
<sensor2>
    <id>T12</id>
    <description>Temperature2</description>
    <value1>23</value1>
</sensor2>
<sensor3>
    <id>T13</id>
    <description>Temperature3</description>
    <value>0</value>
</sensor3>