Tree style gridview_问答_开发者_运维开发者技术经验分享

Does anybody know a gridview for c# w开发者_运维知识库eb applications or ajax that shows data as a tree?
For example I have some general information about contacts and I want to show each row has extra information like activity for that contact and ability to hide or show extra information.
Ordering to relational database model!
Have it from somewhere in the inet... I think it was from Dino Esposito this control...
// The DataSource SHOULD BE a DataSet. 
// No check is implemented on this point.

namespace EnterpriseUtilities.Webcontrols
{
    /// <summary>
    /// Creates a nested data grid.
    /// </summary>
    public class NestedDataGrid : System.Web.UI.WebControls.DataGrid
    {
        /// <summary>
        /// The width.
        /// </summary>
        public Unit HostColumnWidth;
        private DataGrid detailsGrid;
        /// <summary>
        /// Gets or sets the item to render expanded.
        /// </summary>
        public int ExpandedItem
        {
            get {return Convert.ToInt32(ViewState["ExpandedItem"]);}
            set {ViewState["ExpandedItem"] = value;}
        }
        /// <summary>
        /// Gets or sets whether the child grid is scrollable or pageable
        /// </summary>
        public bool ScrollChildren
        {
            get {return Convert.ToBoolean(ViewState["ScrollChildren"]);}
            set {ViewState["ScrollChildren"] = value;}
        }
        /// <summary>
        /// Gets or sets the name of the DataSet's relation to use to fill the subgrid.
        /// </summary>
        public string RelationName
        {
            get {return Convert.ToString(ViewState["RelationName"]);}
            set {ViewState["RelationName"] = value;}
        }
        /// <summary>
        /// Fire the UpdateView event to the page for binding.
        /// </summary>
        public event EventHandler UpdateView;
        private void OnUpdateView()
        {
            if (UpdateView != null)
                UpdateView(this, EventArgs.Empty); 
        }
        /// <summary>
        /// Public ctor
        /// </summary>
        public NestedDataGrid() : base()
        {
            ExpandedItem = -1;
            HostColumnWidth = Unit.Pixel(150);
            ScrollChildren = true;

            AllowPaging = true;
            PageIndexChanged += new DataGridPageChangedEventHandler(NestedDataGrid_PageIndexChanged);
            ItemCommand += new DataGridCommandEventHandler(NestedDataGrid_ItemCommand);
            ItemDataBound += new DataGridItemEventHandler(NestedDataGrid_ItemDataBound);
        }
        /// <summary>
        /// Page change handler.
        /// </summary>
        /// <param name="sender">The sender.</param>
        /// <param name="e">The page changed event.</param>
        private void NestedDataGrid_PageIndexChanged(object sender, DataGridPageChangedEventArgs e)
        {
            CurrentPageIndex = e.NewPageIndex;
            SelectedIndex = -1;
            EditItemIndex = -1;
            ExpandedItem = -1;

            OnUpdateView();
        }
        /// <summary>
        /// Command handler.
        /// </summary>
        /// <param name="source">The sender.</param>
        /// <param name="e">The event args.</param>
        private void NestedDataGrid_ItemCommand(object source, DataGridCommandEventArgs e)
        {
            if (e.CommandName != "Expand")
                return;

            ExpandItem(e.Item);
        }
        /// <summary>
        /// Adjust the index of the expanded item.
        /// </summary>
        /// <param name="item">The item.</param>
        private void ExpandItem(DataGridItem item)
        {
            if (item.ItemIndex == (ExpandedItem % this.PageSize))
                SetExpandedItem(item, false);
            else
                SetExpandedItem(item, true);

            OnUpdateView();
        }
        /// <summary>
        /// Adjust the index of the expanded item
        /// </summary>
        /// <param name="item">The item.</param>
        /// <param name="expand">If true then item is expanded.</param>
        private void SetExpandedItem(DataGridItem item, bool expand)
        {
            if (expand)
                ExpandedItem = (this.PageSize*this.CurrentPageIndex+item.ItemIndex); 
            else
                ExpandedItem = -1;
        }
        /// <summary>
        /// Opens the subtree and shows the related records.
        /// </summary>
        /// <param name="item">The item.</param>
        /// <param name="columns">The associated columns.</param>
        protected override void InitializeItem(DataGridItem item, DataGridColumn[] columns)
        {
            for (int i=0; i<columns.Length; i++)
            {
                TableCell cell = new TableCell();
                if (columns[i] is ExpandCommandColumn)
                    ((ExpandCommandColumn)columns[i]).InitializeCell(cell, i, item.ItemType, (item.ItemIndex==(ExpandedItem % this.PageSize)));
                else
                    columns[i].InitializeCell(cell, i, item.ItemType);
                item.Cells.Add(cell);
            }
        }
        /// <summary>
        /// Modify the layout of the cell being expanded.
        /// </summary>
        /// <param name="sender">The sender.</param>
        /// <param name="e">The event args.</param>
        private void NestedDataGrid_ItemDataBound(object sender, DataGridItemEventArgs e)
        {
            // Process only items and alternating items
            if (e.Item.ItemType != ListItemType.Item &&
                e.Item.ItemType != ListItemType.AlternatingItem)
                return;

            // Default if the item doesn't have to be expanded
            if (e.Item.ItemIndex != (ExpandedItem % this.PageSize))
            {
                // Instead of itemstyle-width set declaratively
                e.Item.Cells[1].Width = HostColumnWidth;

                return;
            }

            // Build the subtree
            BuildChildLayout(e.Item);
        }
        /// <summary>
        /// Modify the layout of the cell being expanded.
        /// </summary>
        /// <param name="item">The item.</param>
        private void BuildChildLayout(DataGridItem item)
        {
            DataGridItem row = item;

            // Assumes the Expand column is the first

            // Remove all cells but one
            int cellsToSpanOver = row.Cells.Count-1;
            ArrayList listOfText = new ArrayList();
            ArrayList listOfWidth = new ArrayList();
            for (int i=row.Cells.Count-1; i>0; i--)
            {
                listOfText.Add(row.Cells[i].Text);
                if (i==1) // Add the width of the column whose width is not declared
                    listOfWidth.Add(HostColumnWidth);
                else
                    listOfWidth.Add(this.Columns[i].ItemStyle.Width);
                row.Cells.RemoveAt(i);
            }

            // Add the new cell that will host the child grid
            TableCell newCell = new TableCell();
            newCell.ColumnSpan = cellsToSpanOver;
            newCell.BackColor = Color.SkyBlue;

            // MUST BE empty. If you set a fixed width declaratively that value
            // will override this one. For this reason, we set the width of the 
            // first column after the EXPAND column dynamically. We also assume
            // that the first column after the EXPAND column is the host cell, where
            // the child grid is inserted.
            newCell.Width = Unit.Empty;
            row.Cells.Add(newCell);

            // The child layout is made of a 2-row table: header (same as the 
            // previous unexpanded row) and the subgrid
            Table t = new Table();
            t.Font.Name = this.Font.Name;
            t.Font.Size = this.Font.Size;
            t.CellSpacing = this.CellSpacing;
            t.CellPadding = this.CellSpacing;
            t.BorderWidth = this.BorderWidth;

            TableRow rowHeader = new TableRow();
            t.Rows.Add(rowHeader);
            TableRow rowSubGrid = new TableRow();
            t.Rows.Add(rowSubGrid);
            newCell.Controls.Add(t);

            // Fill the header row
            for (int i=listOfText.Count-1; i>=0; i--)
            {
                TableCell c = new TableCell();
                c.Text = listOfText[i].ToString();
                c.Width = (Unit) listOfWidth[i];
                rowHeader.Cells.Add(c);
            }


            // Fill the second row
            Panel outerPanel = null;
            if (ScrollChildren)
            {
                outerPanel = new Panel();
                outerPanel.Height = Unit.Pixel(100);
                outerPanel.Style["overflow"] = "auto"; 
            }

            TableCell cellSubGrid = new TableCell();
            cellSubGrid.ColumnSpan = cellsToSpanOver;
            cellSubGrid.BackColor = Color.LightCyan;
            rowSubGrid.Cells.Add(cellSubGrid);

            detailsGrid = new DataGrid();
            detailsGrid.ID = "detailsGrid";
            detailsGrid.BackColor = Color.LightCyan;
            detailsGrid.Font.Name = this.Font.Name;
            detailsGrid.Font.Size = this.Font.Size;
            detailsGrid.HeaderStyle.Font.Bold = true; 
            detailsGrid.Width = Unit.Percentage(100);

            if (!ScrollChildren)
            {
                detailsGrid.AllowPaging = true;
                detailsGrid.PageSize = 5;
                detailsGrid.PageIndexChanged += new DataGridPageChangedEventHandler(detailsGrid_PageIndexChanged);
            }
            BindDetails(detailsGrid);

            if (ScrollChildren)
            {
                outerPanel.Controls.Add(detailsGrid);
                cellSubGrid.Controls.Add(outerPanel);
            }
            else
            {
                cellSubGrid.Controls.Add(detailsGrid);
            }
        }       
        /// <summary>
        /// Bind the child view to the subgrid.
        /// </summary>
        /// <param name="detailsGrid">The grid.</param>
        private void BindDetails(DataGrid detailsGrid)
        {
            DataSet ds = (DataSource as DataSet);
            if (ds == null)
                return;

            DataTable dt = ds.Tables[this.DataMember];
            DataView theView = new DataView(dt);
            DataRowView drv = theView[ExpandedItem];     
            DataView detailsView = drv.CreateChildView(this.RelationName);

            detailsGrid.DataSource = detailsView;
            detailsGrid.DataBind();
        }
        /// <summary>
        /// Takes care of paging the child grid.
        /// </summary>
        /// <param name="sender">The sender.</param>
        /// <param name="e">The event args.</param>
        private void detailsGrid_PageIndexChanged(object sender, DataGridPageChangedEventArgs e)
        {
            DataGrid detGrid = (DataGrid) sender;
            detGrid.CurrentPageIndex = e.NewPageIndex;
            //Page.Trace.Warn("Child grid page: " + detGrid.CurrentPageIndex.ToString());
            BindDetails(detGrid);
        }
    }
}
What't wrong with the web TreeView control supplied by the .NET framework?