C#

<code>    // Unordered set
    public class Set<T> : KeyedCollection<T, T>
    {
        public Set()
            : base( EqualityComparer<T>.Default, -1 )
        {
        }

        public Set( IEqualityComparer<T> comparer )
            : base( comparer, -1 )
        {
        }

        public new void Add( T item )
        {
            if ( !this.Contains(item ) )    // throws a non-documented exception otherwise.
                base.Add( item );
        }

        public void AddRange( IEnumerable<T> enumerable )
        {
            foreach ( T item in enumerable )
                this.Add( item );
        }

        override protected T GetKeyForItem( T item )
        {
            return item;
        }
    }
</code>

sharpiesharpie wrote:

The problem is that it overwrites the previous text in the file every time, is there a way to append the text?

docXML.Load(s_FileName);

sharpiesharpie wrote:

and is there a better way to save the information?

private void Serialize(object obj, Stream s)
{
  XmlSerializer serializer = new XmlSerializer(obj.GetType());
  serializer(s, obj);
}

[Serializable]
public sealed class Reminder
{
    public string Name;
    public string Date;
    public string Time;
    public string Comment;
}

string s_FileName = Application.StartupPath + "\\List.xml";
                    Reminder r = new Reminder();
                    r.Name = Add.s_Name;
                    r.Date = Add.s_Date;
                    r.Time = Add.s_Time;
                    r.Comment = Add.s_Comment;
                    XmlSerializer xs = new XmlSerializer(typeof(Reminder));
                    FileStream fs = new FileStream(s_FileName, FileMode.OpenOrCreate, FileAccess.Write);
                    xs.Serialize(fs, r);

public sealed class Reminder
{        
	public string Name
	{
		get { return this.name; }
		set { this.name= value; }
	}
	private string name;

	...
}

sharpiesharpie wrote:

when a reminder is added it's saved to the xml file and then the list loads it

string s_FileName = Application.StartupPath + "\\List.xml";
            FileStream fs = new FileStream(s_FileName, FileMode.Create, FileAccess.Write);
            ArrayList al = new ArrayList();
            foreach (ListViewItem i in listView1.Items)
            {
                Reminder r = new Reminder();
                r.Name = i.Text;
                r.Date = i.SubItems[1].Text;
                r.Time = i.SubItems[2].Text;
                r.Comment = i.SubItems[3].Text;
                al.Add(r);
            }
            XmlSerializer xs = new XmlSerializer(typeof(ArrayList));
            xs.Serialize(fs, al);

lb.Items[2]="new text for line 2";
lb.Items[lb.SelectedIndex]="new text for the selected line";