protected void Page_Load(object sender, EventArgs e)
    {
        foreach (ListItem cbox in cboxList.Items)
        {
            if (cbox.Selected)
            {
                Response.Write(cbox.Text+"选中了<br/>");
            }
        }
        BindData();
    }

    protected void BindData()
    {
        cboxList.DataSource = GetData();
        cboxList.DataTextField = "Name";
        cboxList.DataValueField = "Id";
        cboxList.DataBind();

        //随便设置选中几个，然后在设置字体为红色
        foreach (ListItem cbox in cboxList.Items)
        {
            if (Convert.ToInt32(cbox.Value) % 2 == 0)
            {
                cbox.Attributes.Add("style", "color:red;");
            }
        }
    }

    private DataTable GetData()
    {
        DataTable dt = new DataTable();

        dt.Columns.Add("Id", typeof(int));
        dt.Columns.Add("Name", typeof(string));

        dt.Rows.Add(1, "2012-2-1");
        dt.Rows.Add(2, "2012-2-2");
        dt.Rows.Add(3, "2012-2-3");
        dt.Rows.Add(4, "2012-2-4");
        dt.Rows.Add(5, "2012-2-5");
        dt.Rows.Add(6, "2012-2-1");
        dt.Rows.Add(7, "2012-2-2");
        dt.Rows.Add(8, "2012-2-2");
        dt.Rows.Add(9, "2012-2-1");

        return dt;
    }