接上文
有了这两个辅助类后，我们在写我们的ColorfulListBox，代码如下：

ColorfulListBox#region ColorfulListBox
using System;
using System.IO;
using System.Text;
using System.Drawing;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.ComponentModel;
using System.Collections;

namespace CustomizeControls
{
/**//// <summary>
/// Summary description for ColorfulListBox.
/// </summary>
[DefaultProperty("Text"),
ToolboxData("<{0}:ColorfulListBox runat="server"></{0}:ColorfulListBox>")]
public class ColorfulListBox : System.Web.UI.WebControls.ListBox
{
   private ItemColorCollection m_ItemsColor;

   public ColorfulListBox()
    {
      m_ItemsColor = new ItemColorCollection();
     }

   public ItemColorCollection ItemsColor
    {
     get
    {
       m_ItemsColor.Count = this.Items.Count;
       return m_ItemsColor;
     }
  }
/**//// <summary>
/// Render this control to the output parameter specified.
/// </summary>
/// <param name="output"> The HTML writer to write out to </param>
protected override void Render(HtmlTextWriter output)
{
   this.RenderBeginTag(output);
   StringBuilder strbStyle = new StringBuilder();
   for( int i=0 ; i < this.Items.Count ; ++i )
   {
     ListItem li = this.Items[i];
     output.Write("<option value="" + li.Value + """);
     if ( this.SelectedIndex == i )
     {
       output.Write(" selected="selected"");
      }
        /**//*foreach( string strKey in li.Attributes.CssStyle.Keys )
     {
      strbStyle.Append(String.Format("{0}:{1};", strKey,
      li.Attributes.CssStyle[strKey]));
       }
   if ( strbStyle.Length > 0 )
   {
     strbStyle.Insert(0, " style="");
     strbStyle.Append(""");
     output.Write(strbStyle.ToString());
     strbStyle.Remove(0, strbStyle.Length);
   }*/
   if ( m_ItemsColor[i] != null )
   {
   Color cForeColor = m_ItemsColor[i].ForeColor;
   if ( cForeColor != Color.Empty )
   {
     strbStyle.Append(String.Format("color:{0};", cForeColor.Name));
   }
    Color cBackColor = m_ItemsColor[i].BackColor;
     if ( cBackColor != Color.Empty )
     {
       strbStyle.Append(String.Format("background-color:{0}", cBackColor.Name));
     }
     if ( strbStyle.Length > 0 )
     {
     strbStyle.Insert(0, " style="");
     strbStyle.Append(""");
     output.Write(strbStyle.ToString());
     strbStyle.Remove(0, strbStyle.Length);
     }
    }
   output.Write(">" + li.Text + "</option> ");
    }
   this.RenderEndTag(output);
    }
  }
}
#endregion

编译好我们的ColorfulListBox后，其他项目中引用ColorfulListBox.dll，就可以在工具箱中拖出ColorfulListBox，我们可以这样给一个ListBox设置每个Item的颜色了：

clstb.ItemsColor[3].ForeColor = Color.Red;
clstb.ItemsColor[2].BackColor = Color.Yellow;
clstb.ItemsColor[2].ForeColor = Color.Black;
clstb.ItemsColor[1].ForeColor = Color.Blue;

ColorfulListBox效果示例：
Color: <Not Set>AliceBlue AntiqueWhite Aqua Aquamarine Azure Beige Bisque Black BlanchedAlmond Blue BlueViolet Brown BurlyWood CadetBlue Chartreuse Chocolate Coral CornflowerBlue Cornsilk Crimson Cyan DarkBlue DarkCyan DarkGoldenrod DarkGray DarkGreen DarkKhaki DarkMagenta DarkOliveGreen DarkOrange DarkOrchid DarkRed DarkSalmon DarkSeaGreen DarkSlateBlue DarkSlateGray DarkTurquoise DarkViolet DeepPink DeepSkyBlue DimGray DodgerBlue Firebrick FloralWhite ForestGreen Fuchsia Gainsboro GhostWhite Gold Goldenrod Gray Green GreenYellow Honeydew HotPink IndianRed Indigo Ivory Khaki Lavender LavenderBlush LawnGreen LemonChiffon LightBlue LightCoral LightCyan LightGray LightGoldenrodYellow LightGreen LightPink LightSalmon LightSeaGreen LightSkyBlue LightSlateGray LightSteelBlue LightYellow Lime LimeGreen Linen Magenta Maroon MediumAquamarine MediumBlue MediumOrchid MediumPurple MediumSeaGreen MediumSlateBlue MediumSpringGreen MediumTurquoise MediumVioletRed MidnightBlue MintCream MistyRose Moccasin NavajoWhite Navy OldLace Olive OliveDrab Orange OrangeRed Orchid PaleGoldenrod PaleGreen PaleTurquoise PaleVioletRed PapayaWhip PeachPuff Peru Pink Plum PowderBlue Purple Red RosyBrown RoyalBlue SaddleBrown Salmon SandyBrown SeaGreen SeaShell Sienna Silver SkyBlue SlateBlue SlateGray Snow SpringGreen SteelBlue Tan Teal Thistle Tomato Transparent Turquoise Violet Wheat White WhiteSmoke Yellow YellowGreen 

That's all.