C# ListBox.GetItemRectangle方法代码示例

        /// <summary>
        /// Show a listbox with possible completions for the uncompleted string.
        /// When the user chooses one and presses enter (or clicks it with the mouse),
        /// return the chosen completion. Or, when the user presses escape, then 
        /// close the window and return null.
        /// </summary>        
        public string ShowTooltip(string uncompleted, IEnumerable<string> completions, IEnumerable<string> documentations,Point location)
        {
            _lstCompletions = new ListBox();
            _lstCompletions.ScrollAlwaysVisible = true;
            _lstCompletions.Items.AddRange(completions.ToArray());
            _lstCompletions.SelectionMode = SelectionMode.One;
            _lstCompletions.AutoSize = false;
            _lstCompletions.SelectedIndexChanged += new EventHandler(selectedIndexChanged);
            _lstCompletions.Click += new EventHandler(lstCompletionsClicked);

            int maxWidth = 0;
            for (int i = 0; i < _lstCompletions.Items.Count; i++)
            {
                if (_lstCompletions.GetItemRectangle(i).Width > maxWidth)
                    maxWidth = _lstCompletions.GetItemRectangle(i).Width;
            }
            _lstCompletions.Width = maxWidth;
            if (_lstCompletions.Items.Count > 0)
                _lstCompletions.Height = _lstCompletions.GetItemHeight(0) * 10;

            _documentations = documentations;
            _lblDocumentation = new TextBox();
            _lblDocumentation.WordWrap = true;
            _lblDocumentation.Width = _lstCompletions.Width;
            _lblDocumentation.BackColor = SystemColors.ControlLight;
            if (_documentations!=null && _documentations.Count() > 0)
                _lblDocumentation.Text = _documentations.ElementAt(0);
            _lblDocumentation.ScrollBars = ScrollBars.Vertical;
            _lblDocumentation.Multiline = true;
            _lblDocumentation.AutoSize = true;
            _lblDocumentation.Height = 100;
            _lblDocumentation.ReadOnly = true;

            _dialog = new CompletionToolTipWindow(_lstCompletions,_lblDocumentation);
            _dialog.KeyDown += new KeyEventHandler(dialog_KeyDown);
            _dialog.Location = location;
            _dialog.KeyPreview = true;
            _dialog.ShowDialog();

            if (_cancel || _lstCompletions.SelectedIndex < 0)
                return null;

            return (string)_lstCompletions.SelectedItem;
        }

        // For List Boxes -- TODO Need to make this work with prefereneces for UseCheckmark
        public static void DrawItem(this DrawItemEventArgs e, string text, Color color, ListBox lb, bool useCheckmark)
        {
            e.DrawBackground();

            var selected = (e.State & DrawItemState.Selected) == DrawItemState.Selected;
            GenericBrush.Color = color;
            e.Graphics.FillRectangle(selected && !useCheckmark ? SystemBrushes.Highlight : GenericBrush, e.Bounds);
            var contrastingBrush = selected && !useCheckmark ? SystemBrushes.HighlightText : color.GetTextColor();
            e.Graphics.DrawString(text, e.Font, contrastingBrush, lb.GetItemRectangle(e.Index).Location);

            if (selected && useCheckmark) {
                e.Graphics.DrawString(Checkmark, e.Font, contrastingBrush, e.Bounds.Width - e.Bounds.Height, e.Bounds.Y);
            }

            e.DrawFocusRectangle();
        }

        private Rectangle GetCheckBoxRectangleForListBoxItem(ListBox currentListBox, int itemIndex)
        {
            const int edgeMargin = 8;

            Rectangle itemRectangle = currentListBox.GetItemRectangle(itemIndex);

            // this is the bound of the checkbox
            var checkBoxRectangle = new Rectangle(
                itemRectangle.Left + edgeMargin + 2,
                itemRectangle.Top + edgeMargin,
                _checkBoxSize.Width,
                _checkBoxSize.Height);

            return checkBoxRectangle;
        }

        public TipWindow( ListBox listbox, int index )
        {
            InitializeComponent();
            InitControl( listbox );

            this.itemBounds = listbox.GetItemRectangle( index );
            this.tipText = listbox.Items[ index ].ToString();
        }

 private int GetItemAt(ListBox listBox, int X, int Y)
 {
     int index = -1;
     for (int i = 0; i < listBox.Items.Count; i++)
     {
         System.Drawing.Rectangle r = listBox.GetItemRectangle(i);
         if (r.Contains(new Point(X, Y)))
         {
             index = i;
             break;
         }
     }
     return index;
 }

 private int HandleListboxClick(ListBox lb, Rectangle clickloc)
 {
     for (var a = 0; a < lb.Items.Count; a++)
     {
         var a1 = lb.GetItemRectangle(a);
         var r = new Rectangle(lb.Location.X + a1.X, lb.Location.Y + a1.Y, a1.Width, a1.Height);
         if (r.Intersects(clickloc))
         {
             lb.SelectedIndex = a;
             return a;
         }
     }
     lb.SelectedIndex = -1;
     return -1;
 }