tabstrip.cs

浏览器端看到树型目录结构,用户可以完整地看到像windows资源管理器一样的效果

            if (target != null)
            {
                if (_OldMultiPageIndex < 0)
                {
                    SetTargetSelectedIndex();
                }

                if ((_OldMultiPageIndex >= 0) && (target.SelectedIndex != _OldMultiPageIndex))
                {
                    target.FireSelectedIndexChangeEvent();
                }
            }
        }

        /// <summary>
        /// Overridden. Creates an EmptyControlCollection to prevent controls from
        /// being added to the ControlCollection.
        /// </summary>
        /// <returns>An EmptyControlCollection object.</returns>
        protected override ControlCollection CreateControlCollection()
        {
            return new EmptyControlCollection(this);
        }

        /// <summary>
        /// Overridden. Verifies certain properties.
        /// </summary>
        /// <param name="e">An EventArgs object that contains the event data.</param>
        protected override void OnInit(EventArgs e)
        {
            // It may have been possible for a SelectedIndex to be assigned
            // before our Items were added. In that case, we cached the
            // SelectedIndex, and now we're going to do the assignment.
            if (_CachedSelectedIndex != NotSet)
            {
                SelectedIndex = _CachedSelectedIndex;
                _CachedSelectedIndex = NotSet;
            }

            base.OnInit(e);
        }

        /// <summary>
        /// Overriden. Verifies certain properties.
        /// </summary>
        /// <param name="e">An EventArgs object that contains the event data.</param>
        protected override void OnLoad(EventArgs e)
        {
            if ((Page != null) && !Page.IsPostBack)
            {
                if ((TargetID != String.Empty) && (Target == null))
                {
                    // TargetID cannot be found
                    throw new Exception(GetStringResource("TabStripInvalidTargetID"));
                }

                foreach (TabItem item in Items)
                {
                    if (item is Tab)
                    {
                        Tab tab = (Tab)item;
                        PageView target = tab.Target;

                        if ((tab.TargetID != String.Empty) && (target == null))
                        {
                            // TargetID cannot be found
                            throw new Exception(GetStringResource("TabInvalidTargetID"));
                        }
                    }
                }

                SetTargetSelectedIndex();
            }

            base.OnLoad(e);
        }

        /// <summary>
        /// Overridden. Updates the hidden input's data.
        /// </summary>
        /// <param name="e">An EventArgs object that contains the event data.</param>
        protected override void OnPreRender(EventArgs e)
        {
            HelperData = SelectedIndex.ToString();

            base.OnPreRender(e);
        }

        /// <summary>
        /// Overridden. Renders the TabItems within the Items collection.
        /// </summary>
        /// <param name="writer">The output stream that renders HTML content to the client.</param>
        protected override void RenderContents(HtmlTextWriter writer)
        {
            foreach (TabItem item in Items)
            {
                item.Render(writer, RenderPath);
            }
        }

        /// <summary>
        /// The rendering path for uplevel browsers.
        /// </summary>
        /// <param name="writer">The output stream that renders HTML content to the client.</param>
        protected override void RenderUpLevelPath(HtmlTextWriter writer)
        {
            writer.Write("<?XML:NAMESPACE PREFIX=\"" + TagNamespace
                + "\" /><?IMPORT NAMESPACE=\"" + TagNamespace + "\" IMPLEMENTATION=\""
                + AddPathToFilename("tabstrip.htc") + "\" />");
            writer.WriteLine();

            AddAttributesToRender(writer);

            writer.AddAttribute("selectedIndex", SelectedIndex.ToString());

            if (Orientation == Orientation.Vertical)
                writer.AddAttribute("orientation", "vertical");
            if (TargetID != String.Empty)
                writer.AddAttribute("targetID", Target.ClientID);

            if (SepDefaultImageUrl != String.Empty)
                writer.AddAttribute("sepDefaultImageUrl", SepDefaultImageUrl);
            if (SepHoverImageUrl != String.Empty)
                writer.AddAttribute("sepHoverImageUrl", SepHoverImageUrl);
            if (SepSelectedImageUrl != String.Empty)
                writer.AddAttribute("sepSelectedImageUrl", SepSelectedImageUrl);

            string style = TabDefaultStyle.CssText;
            if (style != String.Empty)
                writer.AddAttribute("tabDefaultStyle", style);
            style = TabHoverStyle.CssText;
            if (style != String.Empty)
                writer.AddAttribute("tabHoverStyle", style);
            style = TabSelectedStyle.CssText;
            if (style != String.Empty)
                writer.AddAttribute("tabSelectedStyle", style);
            style = SepDefaultStyle.CssText;
            if (style != String.Empty)
                writer.AddAttribute("sepDefaultStyle", style);
            style = SepHoverStyle.CssText;
            if (style != String.Empty)
                writer.AddAttribute("sepHoverStyle", style);
            style = SepSelectedStyle.CssText;
            if (style != String.Empty)
                writer.AddAttribute("sepSelectedStyle", style);

            if (Page != null)
            {
                string script = ClientHelperID + ".value" + "=event.index";

                if (AutoPostBack)
                {
                    script += ";if (getAttribute('_submitting') != 'true'){setAttribute('_submitting','true');try{" + Page.GetPostBackEventReference(this, String.Empty) + ";}catch(e){setAttribute('_submitting','false');}}";
                }

                writer.AddAttribute("onSelectedIndexChange", "JScript:" + script);
                writer.AddAttribute("onwcready", "JScript:try{" + ClientHelperID + ".value=selectedIndex}catch(e){}");
            }

            writer.RenderBeginTag(TagNamespace + ":" + TabStripTagName);
            writer.WriteLine();

            base.RenderUpLevelPath(writer);

            writer.RenderEndTag();
        }

        /// <summary>
        /// The rendering path for downlevel browsers.
        /// </summary>
        /// <param name="writer">The output stream that renders HTML content to the client.</param>
        protected override void RenderDownLevelPath(HtmlTextWriter writer)
        {
            writer.WriteLine("<script language=\"javascript\">" + ClientHelperID + ".value=" + SelectedIndex.ToString() + ";</script>");

            writer.AddAttribute(HtmlTextWriterAttribute.Cellspacing, "0");
            writer.AddAttribute(HtmlTextWriterAttribute.Cellpadding, "0");
            writer.AddAttribute(HtmlTextWriterAttribute.Border, "0");

            AddAttributesToRender(writer);

            writer.RenderBeginTag(HtmlTextWriterTag.Table);

            if (Orientation == Orientation.Horizontal)
            {
                writer.RenderBeginTag(HtmlTextWriterTag.Tr);
            }
            
            base.RenderDownLevelPath(writer);

            if (Orientation == Orientation.Horizontal)
            {
                writer.RenderEndTag();  // TR
            }
            writer.RenderEndTag();  // TABLE
        }

        /// <summary>
        /// The rendering path for visual designers.
        /// </summary>
        /// <param name="writer">The output stream that renders HTML content to the client.</param>
        protected override void RenderDesignerPath(HtmlTextWriter writer)
        {
            writer.AddAttribute(HtmlTextWriterAttribute.Cellspacing, "0");
            writer.AddAttribute(HtmlTextWriterAttribute.Cellpadding, "0");
            writer.AddAttribute(HtmlTextWriterAttribute.Border, "0");

            AddAttributesToRender(writer);

            writer.RenderBeginTag(HtmlTextWriterTag.Table);

            if (Orientation == Orientation.Horizontal)
            {
                writer.RenderBeginTag(HtmlTextWriterTag.Tr);
            }
            
            base.RenderDesignerPath(writer);

            if (Orientation == Orientation.Horizontal)
            {
                writer.RenderEndTag();  // TR
            }
            writer.RenderEndTag();  // TABLE
        }

        /// <summary>
        /// Loads the control's previously saved view state.
        /// </summary>
        /// <param name="savedState">An object that contains the saved view state values for the control.</param>
        protected override void LoadViewState(object savedState)
        {
            if (savedState != null)
            {
                object[] state = (object[])savedState;

                base.LoadViewState(state[0]);
                ((IStateManager)Items).LoadViewState(state[1]);
                ((IStateManager)TabDefaultStyle).LoadViewState(state[2]);
                ((IStateManager)TabHoverStyle).LoadViewState(state[3]);
                ((IStateManager)TabSelectedStyle).LoadViewState(state[4]);
                ((IStateManager)SepDefaultStyle).LoadViewState(state[5]);
                ((IStateManager)SepHoverStyle).LoadViewState(state[6]);
                ((IStateManager)SepSelectedStyle).LoadViewState(state[7]);
            }
        }

        /// <summary>
        /// Saves the changes to the control's view state to an Object.
        /// </summary>
        /// <returns>The object that contains the view state changes.</returns>
        protected override object SaveViewState()
        {
            object[] state = new object[]
            {
                base.SaveViewState(),
                ((IStateManager)Items).SaveViewState(),
                ((IStateManager)TabDefaultStyle).SaveViewState(),
                ((IStateManager)TabHoverStyle).SaveViewState(),
                ((IStateManager)TabSelectedStyle).SaveViewState(),
                ((IStateManager)SepDefaultStyle).SaveViewState(),
                ((IStateManager)SepHoverStyle).SaveViewState(),
                ((IStateManager)SepSelectedStyle).SaveViewState(),
            };

            // Check to see if we're really saving anything
            foreach (object obj in state)
            {
                if (obj != null)
                {
                    return state;
                }
            }

            return null;
        }

        /// <summary>
        /// Instructs the control to track changes to its view state.
        /// </summary>
        protected override void TrackViewState()
        {
            base.TrackViewState();

            ((IStateManager)TabDefaultStyle).TrackViewState();
            ((IStateManager)TabHoverStyle).TrackViewState();
            ((IStateManager)TabSelectedStyle).TrackViewState();
            ((IStateManager)SepDefaultStyle).TrackViewState();
            ((IStateManager)SepHoverStyle).TrackViewState();
            ((IStateManager)SepSelectedStyle).TrackViewState();
            ((IStateManager)Items).TrackViewState();
        }
    }
}