Trying to update a node value of XML and it's throwing an exception

Question

I'm trying to update a node value from a XML file but when I'm trying to do this action is throwing an exception "Additional information: Object reference not set to an instance of an object."

This is what I have:

public void UpdateXMLValues(List<string> values)
{
    XmlNode node;
    xmldoc = new XmlDocument();
    xmldoc.Load(XMLInterfaces);
    node = xmldoc.SelectSingleNode("Servers/MYSERVER");
    XMLValues = new List<string>(values);
    node.Attributes["Host"].Value = XMLValues[0];
    xmldoc.Save(XMLInterfaces);
}

and this is my XML information:

<Servers>
  <MYSERVER>
    <Host>0.0.0.0</Host>
    <Port>23</Port>
    <User>TestingUser</User>
    <Password>/NNfWRStbZsUyc88S5tjhA==</Password>
  </MYSERVER>
</Servers>

When I press F11 in the line node.Attributes["Host"].values = XMLValues[0]; I'm getting the error

any idea?

Looks like your xml is not valid, needs either a closing tag or it needs to be self-closing — JanR, Mar 03 '16 at 22:58
Sorry! It has the close label, just I didn't add here in my example... — Javier Salas, Mar 03 '16 at 22:59
Can you update your question with the proper xml? Where does the closing tag sit? — JanR, Mar 03 '16 at 23:00

RB. · Answer 1 · 2016-03-03T23:06:47.457

2

Host is not an attribute of the MYSERVER element. It's an element inside it.

You can access it like so:

var hostNode = node["Host"];
hostNode.Value = XMLValues[0];

For reference, if it was an attribute, your XML would look like this:

<MYSERVER host="some_host">
</MYSERVER>

edited Mar 03 '16 at 23:06

answered Mar 03 '16 at 23:03

RB.

33,692
12
79
121

If is not an attribute, then how could i update that value? – Javier Salas Mar 03 '16 at 23:05
I've updated the question to include how to update the value. – RB. Mar 03 '16 at 23:07
I'm getting this using this solution: var hostNode = node["Host"]; hostNode.Value = XMLValues[0]; – Javier Salas Mar 03 '16 at 23:15
@JavierSalas Errr - do you have an error or something? I'm not really sure what you're saying. – RB. Mar 04 '16 at 09:25

Trying to update a node value of XML and it's throwing an exception

1 Answers1