xml File content:

<?xml version="1.0" encoding="utf-8"?>
<subtitles>
<info>
<content> Latest Announcements: 51 Have a holiday 7 Day! Please be informed by teachers </content>
<speed>4</speed>
<color>red</color>
</info>
</subtitles>

C # code:

XmlDocument xml = new XmlDocument();
xml.Load(context.Server.MapPath("~/js/XMLFile.xml"));
XmlNode xn = xml.DocumentElement;
foreach (XmlNode node in xn.ChildNodes)
{
if (node.Name == "info")
{
node["content"].InnerText = content;
node["speed"].InnerText = speed;
node["color"].InnerText = color;
}
}
xml.Save(context.Server.MapPath("~/js/XMLFile.xml"));

Two other approaches: Modify the property value of a node in the xml string as follows:

XmlDocument doc = new XmlDocument();
doc.LoadXml("<fsdlconfig userName=\"ss\" password=\"134\"/>");
XmlAttribute att =(XmlAttribute)doc.SelectSingleNode("/fsdlconfig/@userName");
Console.WriteLine(att.Value);
att.Value = "test";
string str = doc.OuterXml;

The value of the node userName changed from “ss” to “test”, and then saved the modified xml as a string with doc.OuterXml. Another way:

XmlDocument doc = new XmlDocument();
doc.LoadXml("<fsdlconfig userName=\"ss\" password=\"134\"/>");
XmlElement att = (XmlElement)doc.FirstChild;
att.SetAttribute("userName","test");
string str = doc.OuterXml;