XML file creation using XDocument in C#

LINQ to XML allows this to be much simpler, through three features:

• You can construct an object without knowing the document it's part of
• You can construct an object and provide the children as arguments
• If an argument is iterable, it will be iterated over

So here you can just do:

void Main()
{
    List<string> list = new List<string>
    {
        "Data1", "Data2", "Data3"
    };

    XDocument doc =
      new XDocument(
        new XElement("file",
          new XElement("name", new XAttribute("filename", "sample")),
          new XElement("date", new XAttribute("modified", DateTime.Now)),
          new XElement("info",
            list.Select(x => new XElement("data", new XAttribute("value", x)))
          )
        )
      );

    doc.Save("Sample.xml");
}

I've used this code layout deliberately to make the code itself reflect the structure of the document.

If you want an element that contains a text node, you can construct that just by passing in the text as another constructor argument:

// Constructs <element>text within element</element>
XElement element = new XElement("element", "text within element");