C# How to change Xml node values using Linq

Question

How can I replace the node value some value with another value using Linq. Finally I need a string with the replaced value.

Xml:

<ROOT>
  <A>
    <A1>
      <elementA1></elementA1>
    </A1>
    <A2>
      <elementA2>some value</elementA2>
    </A2>
  </A>
</ROOT>

C#:

XDocument xDoc = XDocument.Parse(@"<ROOT>
                                        <A>
                                          <A1>
                                            <elementA1></elementA1>
                                          </A1>
                                          <A2>
                                            <elementA2>Some value</elementA2>
                                          </A2>
                                        </A>
                                      </ROOT>");

xDoc.Elements("ROOT")
             .Elements("A")
             .Elements("A2")
             .Elements("elementA2")
             .Select(e => e.Value).ToList().ForEach(e => /* change the value */);

Answer 1

You can use the XPathSelectElement method for this:

var newValue = "New value";

var xDoc = XDocument.Parse(@"<ROOT>
    <A>
        <A1>
            <elementA1></elementA1>
        </A1>
        <A2>
            <elementA2>Some value</elementA2>
        </A2>
    </A>
</ROOT>");

xDoc.XPathSelectElement("/ROOT/A/A2/elementA2").SetValue(newValue);

Answer 2

不要从所有节点中选择Value，而要获取节点本身并更改Value属性。