C#

Mika Wendelius wrote:

it depends on (all of) your requirements.

public class CClub
{
    int m_id;
    string m_name;

    public string GenerateXml()
    {
        return 
            "<Club ID=\"" + m_id.ToString() + "\">\n" +
                "<Name>" + m_name + "</Name>\n" +
            "</Club>\n";
    }
}

public class CClub
{
    int m_id;
    string m_name;

    public void ReadXml(XmlElement element)
    {
        m_id = Convert.ToInt32(element.GetAttribute("Club"));

        foreach (XmlNode node in element.ChildNodes)
        {
            if (node.NodeType == XmlNodeType.Element &&
                node.Name == "Club")
            {
                m_name = node.InnerText;
            }
        }
    }

    public void WriteXml(XmlNode parentNode)
    {
        XmlElement element = parentNode.OwnerDocument.CreateElement("Club");
        parentNode.AppendChild(element);

        // Save the ID
        element.SetAttribute("Club", m_id.ToString());

        // Save the name
        XmlElement elementName = parentNode.OwnerDocument.CreateElement("Name");
        element.AppendChild(elementName);
        elementName.InnerText = m_name;
    }
}

public class CDepartment
{
    CDepartmentInfo m_departmentInfo;
    CClubs          m_clubs;
    CTeachers       m_teachers;

    public void ReadXml(XmlDocument element)
    {
        foreach (XmlNode node in element.ChildNodes)
        {
            if (node.NodeType == XmlNodeType.Element)
            {
                switch (node.Name)
                {
                    case "DepartmentInfo":
                        m_departmentInfo = new CDepartmentInfo();
                        m_departmentInfo.ReadXml(node as XmlElement);
                    case "Clubs":
                        m_clubs = new CClubs();
                        m_clubs.ReadXml(node as XmlElement);
                    case "Teachers":
                        m_teachers = new CTeachers();
                        m_teachers.ReadXml(node as XmlElement);
                }
            }
        }
    }

    public void WriteXml(XmlDocument document)
    {
        m_departmentInfo.WriteXml(document);
        m_clubs.WriteXml(document);
        m_teachers.WriteXml(document);
    }
}

public class DepartmentInfo
{
    public DepartmentInfo(int id,string location,string type) {
        this.Id = id;
        this.Location = location;
        this.Type = type;
    }
    public DepartmentInfo() {

    }
    [XmlAttribute("Id")]
    public int Id { get; set; }
    public string Location { get; set; }
    public string Type { get; set; }
}

public class Club
{
    public Club(int id,string name) {
        this.Id = id;
        this.Name = name;
    }
    public Club() {

    }
    [XmlAttribute("Id")]
    public int Id { get; set; }
    public string Name { get; set; }
}

public class Teacher
{
    public Teacher(int id,string name,string major) {
        this.Id = id;
        this.Name = name;
        this.Major = major;
    }
    public Teacher() {

    }
    [XmlAttribute("Id")]
    public int Id { get; set; }
    public string Name { get; set; }
    public string Major { get; set; }
}

[XmlRoot("Department")]
    public class Department
    {
        public Department(DepartmentInfo info,Club[] clubs,Teacher[] teachers) {
            this.DepartmentInfo = info;
            this.Clubs = clubs;
            this.Teachers = teachers;
        }

        public Department() {
        }

        [XmlElement("DepartmentInfo")]
        public DepartmentInfo DepartmentInfo { get; set; }
        [XmlArray("Clubs")]
        public Club[] Clubs { get; set; }
        [XmlArray("Teachers")]
        public Teacher[] Teachers { get; set; }
    }

static void Main(string[] args) {
    Club[] clubs = { new Club(200, "Football"), new Club(201, "Basketball") };
    Teacher[] teachers = { new Teacher(300, "Thomas", "Algorithm"), new Teacher(301, "Zhou", "Linear Programming") };
    Department department = new Department(new DepartmentInfo(100,"San Jose", "Computer Science"), clubs, teachers);

    XmlSerializer serializer = new XmlSerializer(typeof(Department));
    serializer.Serialize(Console.Out, department);
    Console.Read();
}