Использовать xml linq:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Data;
using System.Xml;
using System.Xml.Linq;
namespace ConsoleApplication78
{
class Program
{
static void Main(string[] args)
{
string xml =
"<?xml version=\"1.0\" encoding=\"UTF-8\"?>" +
"<note>" +
"<to>Tove</to>" +
"<from>Jani</from>" +
"<heading>Reminder</heading>" +
"<body>Don't forget me this weekend!</body>" +
"</note>";
XDocument doc = XDocument.Parse(xml);
XElement from = doc.Descendants("from").FirstOrDefault();
XElement heading = doc.Descendants("heading").FirstOrDefault();
XElement body = doc.Descendants("body").FirstOrDefault();
from.Add(heading);
XElement example = new XElement("example", new object[] {from,body});
heading.Remove();
body.Remove();
from.ReplaceWith(example);
}
}
}
Если вы создаете с нуля
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Data;
using System.Xml;
using System.Xml.Linq;
namespace ConsoleApplication78
{
class Program
{
static void Main(string[] args)
{
string ident = "<?xml version=\"1.0\" encoding=\"UTF-8\"?><note></note>";
XDocument doc = XDocument.Parse(ident);
XElement note = doc.Root;
note.Add(new XElement("to", "Tove"),
new XElement("example", new object[] {
new XElement("from", new object[] {
"Jani", new XElement("heading", "Reminder")
}),
new XElement("body","Don't forget me this weekend!")
})
);
}
}
}