public partial class Form2 : Form
    {
        public Form2()
        {
            InitializeComponent();
            listBox1.DrawMode = DrawMode.OwnerDrawFixed;//设置ListBox中每一项都手动绘制
            listBox1.Items.Add("成功");
            listBox1.Items.Add("失败");
            listBox1.Items.Add("事业");
            listBox1.Items.Add("成仁");
        }
        //绘制ListBox项的方法
        private void listBox1_DrawItem(object sender, DrawItemEventArgs e)
        {
            listBox1.DrawMode = DrawMode.OwnerDrawFixed;
            e.DrawBackground();
            Brush myBrush = Brushes.Black;

            switch (listBox1.Items[e.Index].ToString())
            {
                case "成功":
                    myBrush = Brushes.Blue;
                    Console.WriteLine(listBox1.Items[e.Index].ToString());
                    break;
                case "失败":
                    myBrush = Brushes.Red;
                    Console.WriteLine(listBox1.Items[e.Index].ToString());
                    break;
                default:
                    myBrush = Brushes.Purple;
                    Console.WriteLine(listBox1.Items[e.Index].ToString());
                    break;
            }
            e.Graphics.DrawString(listBox1.Items[e.Index].ToString(), e.Font, myBrush, e.Bounds, StringFormat.GenericDefault);
            e.DrawFocusRectangle();

        }
    }

------解决方案--------------------
设置listbox.DrawMode属性为OwnerDrawFixed
然后添加listbox到drawitem事件
在里面选择哪个item颜色自己设置
  private void listBox1_DrawItem(object sender, DrawItemEventArgs e)
       {
           listBox1.DrawMode = DrawMode.OwnerDrawFixed;
           // Draw the background of the ListBox control for each item.
           e.DrawBackground();
           // Define the default color of the brush as black.
           Brush myBrush = Brushes.Black;

           // Determine the color of the brush to draw each item based on the index of the item to draw.
           switch (e.Index)
           {
               case 0:
                   myBrush = Brushes.Red;
                   break;
               case 1:
                   myBrush = Brushes.Orange;
                   break;
               case 2:
                   myBrush = Brushes.Purple;
                   break;
           }

           // Draw the current item text based on the current Font and the custom brush settings.
           e.Graphics.DrawString(listBox1.Items[e.Index].ToString(), e.Font, myBrush, e.Boun