Adding multiple nodes at once in xml

Question

My xml is this:

<Settings>
    <Ss></Ss>
    <Properties>
        <Property>
            <Name>x</Name>
            <Description>xx</Description>
        </Property>
            <Property>
            <Name>y</Name>
            <Description>yyyyy</Description>
            </Property>
    </Properties>
</Settings>

I want to add as a son of Properties an XElement. This is my code:

XDocument xmlDoc1 = XDocument.Load(@"C:\Users\John\Desktop\FileXml.xml");
xmlDoc1.Element("Properties").Add(new XElement(addManyNodes));

But it doesn't work. It throws null reference exception. Why?

user7116 · Accepted Answer · 2011-10-27 14:43:45Z

2

Because the root of the XDocument is <Settings> and the root itself is not <Properties> you get a null value from Element("Properties").

You need to drill down using XDocument.Root or a chain of calls to Element or Descendants. Here are a few options:

// simplest
xmlDoc1.Root.Element("Properties").Add(new XElement(addManyNodes));

// using a chain of Element calls
xmlDoc1.Element("Settings").Element("Properties").Add(...);

Another way to look at it:

<!-- xmlDoc1 -->
<Settings> <!-- .Root or .Element("Settings") -->
    <Ss></Ss> <!-- .Root.Element("Ss") or .Element("Settings").Element("Ss") -->
    <Properties> <!-- .Root.Element("Properties") -->
        <Property> <!-- .Root.Element("Properties").Element("Property") -->

One final note, if addManyNodes is already an array:

xmlDoc1.Root.Element("Properties").Add(addManyNodes);

Once you've made your changes, you should save it to the file:

xmlDoc1.Save(...);

edited Oct 27, 2011 at 14:43

answered Oct 27, 2011 at 14:37

user7116

64.3k17 gold badges150 silver badges175 bronze badges

Sign up to request clarification or add additional context in comments.

1 Comment

user7116 Over a year ago

I've gone ahead and added some additional info about adding multiple nodes and saving the document when you're through making changes.

Collectives™ on Stack Overflow

Adding multiple nodes at once in xml

1 Answer 1

1 Comment

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

1 Comment

Your Answer

Sign up or log in

Post as a guest

Related