SLイベントの使用

    public partial class BarChart
    {
        private const string Str = " ";

        public BarChart()
        {
            InitializeComponent();
        }

        /// <summary> 
        /// </summary>
        private void OKButton_Click(object sender, RoutedEventArgs e)
        {
            var tp = new TransferParmEventArgs(Str);
            TransferParmEvent(tp);
            DialogResult = true;
        }

        /// <summary>  
        /// </summary>
        protected virtual void TransferParmEvent(TransferParmEventArgs e)
        {
            if (TransferParm != null)
                TransferParm(this, e);
        }
        public event TransferParmEventHandler TransferParm;
        public delegate void TransferParmEventHandler(object sender, TransferParmEventArgs e);
        public sealed class TransferParmEventArgs : EventArgs
        {
            private readonly List<string> _value;
            public TransferParmEventArgs(List<string> value)
            {
                _value = value;
            }
            public List<string> Value
            {
                get { return _value; }
            }
        }
    }

            BarChart bar = new BarChart();
            bar.TransferParm += new BarChart.TransferParmEventHandler(barChart_TransferParm);

        void barChart_TransferParm(object sender, BarChart.TransferParmEventArgs e)
        {
            var str = e.Value;
        }