Kooboo CMS - Html.FrontHtml.Position 详解

        #region Position
        public virtual IHtmlString Position(string positionID)
        {
            return Position(positionID, "");
        }

        public virtual IHtmlString Position(string positionID, string defaultContent)
        {
            return Position(positionID, () => defaultContent);
        }
        public virtual IHtmlString Position(string positionID, Func<string> defaultContentFunc)
        {
            if (PageContext.PageRequestContext.RequestChannel == FrontRequestChannel.Design)
            {
                return new PageDesignHolder(this, positionID);
            }
            else
            {
                var positions = GetContentsForPosition(positionID);
                if (positions.Length == 0)
                {
                    defaultContentFunc = defaultContentFunc == null ? () => "" : defaultContentFunc;
                    return new HtmlString(defaultContentFunc());
                }
                else
                {
                    var htmlStrings = RenderPositionContents(positions).ToArray();
                    return new AggregateHtmlString(htmlStrings);
                }

            }
        }

        public virtual IHtmlString Position(string positionID, bool requireMembershipAuthentication, params string[] membershipGroups)
        {
            if (PageContext.PageRequestContext.RequestChannel == FrontRequestChannel.Design)
            {
                return new PageDesignHolder(this, positionID);
            }
            else
            {
                if (requireMembershipAuthentication)
                {
                    var permission = new PagePermission() { RequireMember = requireMembershipAuthentication, AllowGroups = membershipGroups };
                    if (!permission.Authorize(Html.ViewContext.HttpContext.Membership().GetMember()))
                    {
                        return new HtmlString("");
                    }
                }
                return Position(positionID);
            }
        }