this.tabc_draw.DrawMode = TabDrawMode.OwnerDrawFixed;

void tabc_draw_DrawItem(object sender, DrawItemEventArgs e)
{
    Graphics g = e.Graphics;

    TabPage changedpage = tabc_draw.TabPages[e.Index];//当前处理标签
    Rectangle backrect = tabc_draw.GetTabRect(e.Index);//标签背景区域
    Brush backbrush;//标签背景色
    Brush fontbrush;//标签字体颜色
    Font tabFont;//标签字体
    Pen borderpen;//边框颜色

    //TabControl绘制
    Brush backtabcontrol = new SolidBrush(Color.Black);
    g.FillRectangle(backtabcontrol, this.tabc_draw.ClientRectangle.X + 100, this.tabc_draw.ClientRectangle.Y, this.tabc_draw.ClientRectangle.Size.Width, this.tabc_draw.ItemSize.Height);
    backtabcontrol.Dispose();

    if (e.State == DrawItemState.Selected)
    {
        backbrush = new SolidBrush(Color.Black);
        fontbrush = new SolidBrush(Color.Yellow);
        tabFont = new Font("宋体", 15, FontStyle.Bold, GraphicsUnit.Pixel);
        borderpen = new Pen(Color.LightBlue);
    }
    else
    {
        backbrush = new SolidBrush(Color.White);
        fontbrush = new SolidBrush(Color.Red);
        tabFont = new Font("楷体", 15, FontStyle.Bold, GraphicsUnit.Pixel);
        borderpen = new Pen(Color.DarkGreen);
    }
    //绘制标签背景
    g.FillRectangle(backbrush, backrect);

    //绘制标签字体
    StringFormat _StringFlags = new StringFormat();
    _StringFlags.Alignment = StringAlignment.Center;
    _StringFlags.LineAlignment = StringAlignment.Center;
    g.DrawString(changedpage.Text, tabFont, fontbrush, backrect, new StringFormat(_StringFlags));
    //绘制非标签原始名称【可依据e.State修改】 g.DrawString("呵呵", tabFont, fontbrush, backrect, new StringFormat(_StringFlags));

    //绘制标签边框
    //backrect.Offset(1, 1);
    //backrect.Inflate(2, 2);
    g.DrawRectangle(borderpen, backrect);

    backbrush.Dispose();
    tabFont.Dispose();
    fontbrush.Dispose();
    borderpen.Dispose();
}

//在CodeForm.cs文件的Code属性的set中修改
//修改前：
int preFrom = value.IndexOf(prePrefix);
int fromPos = value.IndexOf(preSuffix);

//修改后：
int preFrom = value.ToLower().IndexOf(prePrefix);
int fromPos = value.ToLower().IndexOf(preSuffix);

//修改SourceCodePluginl.cs文件中的CreateContent方法
public override DialogResult CreateContent(IWin32Window dialogOwner, ref string content)
{
            DialogResult result = DialogResult.Cancel;
            content = HtmlServices.HtmlDecode(content);
            using (CodeForm form = new CodeForm(content))
            {
                result = form.ShowDialog(dialogOwner);
                if (result == DialogResult.OK)
                {
                    content = form.Code;
                }
            }
            return result;
 }