string RenderBrandHTML()
        {
            string ck = prefixBra + _FirstLetter;

            if (_Cache.ContainsKey(ck))
            {
                return(_Cache[ck]);
            }
            List <ProductBrand> brands = ProductBrands.GetBrandsByPY(_FirstLetter);
            string nav = GlobalSettings.RelativeWebRoot + "pages/view.aspx?product-brand";

            if (brands == null || brands.Count == 0)
            {
                return("<div><span>没有可显示的品牌信息!</span></div>");
            }
            StringBuilder sb = new StringBuilder();
            ProductBrand  pb = null;

            int    curCount = brands.Count;
            string catId    = string.Empty;

            sb.AppendLine("<table cellpadding=\"0\" cellspacing=\"0\" class=\"" + _CssClass + "\">");
            for (int i = 0; i < curCount; i++)
            {
                pb = brands[i];
                sb.Append("<tr><td>");
                catId = GlobalSettings.Encrypt(pb.BrandID.ToString());
                sb.AppendLine("<div><a href=\"" + nav + "&ID=" + catId + "\" target=\"_blank\">" + pb.BrandName + "</a></div>");
                sb.AppendLine("</td></tr>");
            }
            sb.AppendLine("</table>");

            if (!_Cache.ContainsKey(ck))
            {
                lock (_lock)
                    if (!_Cache.ContainsKey(ck))
                    {
                        _Cache.Add(ck, sb.ToString());
                    }
            }
            return(sb.ToString());
        }
    public override void OnPageLoaded()
    {
        string letter = this.llCategory.FirstLetter, title = string.Empty;

        StringBuilder sbKeywords = new StringBuilder();

        switch (this.llCategory.LetterType)
        {
        case LettersType.Category:
            List <ProductCategory> listCategory = ProductCategories.GetCategoreisByPY(letter);
            if (null == listCategory || 0 == listCategory.Count)
            {
            }
            else
            {
                foreach (ProductCategory item in listCategory)
                {
                    sbKeywords.AppendFormat("{0},", item.CategoryName);
                }
            }
            title = "分类";
            break;

        case LettersType.Brand:
            List <ProductBrand> listBrand = ProductBrands.GetBrandsByPY(letter);
            if (null == listBrand || 0 == listBrand.Count)
            {
            }
            else
            {
                foreach (ProductBrand item in listBrand)
                {
                    sbKeywords.AppendFormat("{0},", item.BrandName);
                }
            }
            title = "品牌";
            break;

        case LettersType.Industry:
            List <ProductIndustry> listIndustry = ProductIndustries.GetIndustriesByPY(letter);
            if (null == listIndustry || 0 == listIndustry.Count)
            {
            }
            else
            {
                foreach (ProductIndustry item in listIndustry)
                {
                    sbKeywords.AppendFormat("{0},", item.IndustryName);
                }
            }
            title = "行业";
            break;
        }

        string keywords = sbKeywords.ToString().TrimEnd(',');

        if (string.IsNullOrEmpty(keywords))
        {
            //this.AddKeywords(keywords);
            this.AddDescription(string.Format("按照首字母进行{0}检索,首字母是{1}", title, letter.ToUpper()));

            this.ShortTitle = string.Format("首字母{0}检索{1}", title, letter.ToUpper());
        }
        else
        {
            this.AddKeywords(keywords);
            this.AddDescription(string.Format("按照首字母进行{0}检索,首字母是{1},符合条件的{0}列表如下: {2}", title, letter.ToUpper(), keywords));

            this.ShortTitle = string.Format("首字母{0}检索{1} - {2}", title, letter.ToUpper(), keywords);
        }
        this.SetTitle();
    }