XML Serialization for collection types

Question

Does anyone have an implementation for object serialization that support collections, such as ICollection, IEnumerable, IList, IDictionary?

Below is my implementation, and it’s not so clean.

[Serializable]
public abstract class IXmlable
{
    public virtual string ToXml()
    {
        Type type = GetType();
        PropertyInfo[] properties = type.GetProperties();

        string ret = "<" + type.Name + ">";
        foreach (PropertyInfo item in properties)
        {
            object value = item.GetValue(this, null);
            if (value is IConvertible)
                ret += ("<" + item.Name + ">" + (value as IConvertible).ToString(CultureInfo.GetCultureInfo("en-US")) + "</" + item.Name + ">").Replace("&", "&amp;");
            else
                ret += ("<" + item.Name + ">" + (value != null ? value.ToString() : String.Empty) + "</" + item.Name + ">").Replace("&", "&amp;");
        }
        ret += "</" + type.Name + ">";
        return ret;
    }

/// <summary>
/// A class for serializing objects
/// </summary>
public static class Serializer
{
    public static string ToXML<T>(this List<T> parameter)
    {
        return SerializeObject(parameter);
    }

    /// <summary>
    /// This function serialize object.
    /// </summary>
    /// <param name="parameters">The object to be serialize</param>
    /// <returns>Returns the XML presentation of serialized object</returns>
    public static string SerializeObject(params object[] parameters)
    {
        var doc = new XDocument(new XElement("root"));
        string swString = string.Empty;
        foreach (var parameter in parameters)
        {
            var list = parameter as IEnumerable;
            IXmlable xmlable;
            if (list != null)
            {
                Type type = list.GetType().GetGenericArguments()[0];
                if (type.BaseType != null && type.BaseType.Name == "IXmlable")
                {
                    string typeName = type.Name;
                    swString = "<?xml version=\"1.0\"?><ArrayOf" + typeName + " xmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance\" xmlns:xsd=\"http://www.w3.org/2001/XMLSchema\"&gt;";
                    swString = list.Cast<IXmlable>().Aggregate(swString, (current, item) => current + item.ToXml());
                    swString += "</ArrayOf" + typeName + ">";
                }
            }
            else if ((xmlable = parameter as IXmlable) != null)
            {
                swString = xmlable.ToXml();
            }
            else
            {
                swString = Serialize(parameter);
            }

            doc.Root.Add(XDocument.Parse(swString).Root);
        }
        return doc.ToString();
    }

    /// <summary>
    /// Serializes the specified parameter.
    /// </summary>
    /// <param name="parameter">The parameter.</param>
    /// <returns></returns>
    private static string Serialize(object parameter)
    {
        using (var sw = new MemoryStream())
        {
            new XmlSerializer(parameter.GetType()).Serialize(sw, parameter);
            sw.Position = 0;
            var buffer = new byte[sw.Length];
            sw.Read(buffer, 0, (int)sw.Length);
            return Encoding.Default.GetString(buffer);
        }
    }
}

Answer 1

you should have methods like

private static void Save(T yourobject, Type[] extraTypesInyourObject, string path)
{
    using (TextWriter textWriter = new TextWriter(path))
    {
        XmlSerializer xmlSerializer = CreateXmlSerializer(extraTypes);
        xmlSerializer.Serialize(textWriter, yourobject);
    }
}

    private static XmlSerializer CreateXmlSerializer(Type[] extraTypes)
    {
        Type ObjectType = typeof(T);
        XmlSerializer xmlSerializer = null;
        if (extraTypes!=null)
        {
            xmlSerializer = new XmlSerializer(ObjectType, extraTypes);
        }
        else
        {
            xmlSerializer = new XmlSerializer(ObjectType);
        }

        return xmlSerializer;
    }

Answer 2

DataContractSerializer seems to be the best object serializer for the time been. http://msdn.microsoft.com/en-us/library/system.runtime.serialization.datacontractserializer.aspx