Save List<T> to XML file

Question

I want to save records fetched from database in an XML file,
take x number of records from XML file into a custom collection List<T>
process them and save updated items back into XML file.

'T' is a simple object with value type properties, something like -

public class T
{
   public int Id {get; set;}
   public string property1 {get; set;}
   public string property2 {get; set;}
}

Please guide me how can I save custom collection List<T> to XML file and vice-versa?

Also, because I am not sending out this XML file, will it make sense to go for XmlSerializer as suggested in some of the replies?

Answer 1

Here are two methods that we use to accomplish this using the XMLSerializer:

 public static T FromXML<T>(string xml)
 {
     using (StringReader stringReader = new StringReader(xml))
     {
        XmlSerializer serializer = new XmlSerializer(typeof(T));
        return (T)serializer.Deserialize(stringReader);
     }
 }

 public string ToXML<T>(T obj)
 {
    using (StringWriter stringWriter = new StringWriter(new StringBuilder()))
    {
        XmlSerializer xmlSerializer = new XmlSerializer(typeof(T));
        xmlSerializer.Serialize(stringWriter, obj);
        return stringWriter.ToString();
    }
 }

Answer 2

While you could use a serializer - and many times this is the right answer - I personally would use Linq to XML which would allow you to be more flexible on how your XML should look like, i.e. to create the following XML from a collection foos based on your class:

<Foos>
  <foo Id="1" property1="someprop1" property2="someprop2" />
  <foo Id="1" property1="another" property2="third" />
</Foos>

You could use:

var xml = new XElement("Foos", foos.Select( x=> new XElement("foo", 
                                                new XAttribute("Id", x.Id), 
                                                new XAttribute("property1", x.property1), 
                                                new XAttribute("property2", x.property2))));