public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();

            listBox1.DrawMode = System.Windows.Forms.DrawMode.OwnerDrawVariable;
            listBox1.MeasureItem += listBox1_MeasureItem;
            listBox1.DrawItem += listBox1_DrawItem;
        }

        private void listBox1_MeasureItem(object sender, MeasureItemEventArgs e)
        {
            e.ItemHeight = (int)e.Graphics.MeasureString(listBox1.Items[e.Index].ToString(), listBox1.Font, listBox1.Width).Height;
        }

        private void listBox1_DrawItem(object sender, DrawItemEventArgs e)
        {
            e.DrawBackground();
            e.DrawFocusRectangle();
            e.Graphics.DrawString(listBox1.Items[e.Index].ToString(), e.Font, new SolidBrush(e.ForeColor), e.Bounds);
        }
    }