using System;using System.Windows.Forms;using System.Drawing;using System.Runtime.InteropServices;namespace SenseTreeView{    public class SenseTreeView : TreeView    {        #region 控件属性        //显示字体        private Font _NodeFont;        public Font NodeFont        {            get            {                return _NodeFont;            }            set            {                _NodeFont = value;            }        }        //选择TreeView TreeNode时的背景色        private Brush _BackgrountBrush;        public Brush BackgroundBrush        {            get            {                return _BackgrountBrush;            }            set            {                _BackgrountBrush = value;            }        }        //选择TreeView TreeNode时背景色的边框画笔        private Pen _BackgroundPen;        public Pen BackgroundPen        {            get            {                return _BackgroundPen;            }            set            {                _BackgroundPen = value;            }        }        //TreeView中TreeNode展开时的节点显示图标，        private Image _NodeExpandedImage;        public Image NodeExpandedImage        {            get            {                return _NodeExpandedImage;            }            set            {                _NodeExpandedImage = value;            }        }        //TreeView中TreeNode合拢时的节点显示图标        private Image _NodeCollapseImage;        public Image NodeCollapseImage        {            get            {                return _NodeCollapseImage;            }            set            {                _NodeCollapseImage = value;            }        }        //TreeView中TreeNode的节点显示图标的大小        private Size _NodeImageSize;        public Size NodeImageSize        {            get            {                return _NodeImageSize;            }            set            {                _NodeImageSize = value;            }        }        //节点显示图标离左边界的位置        private int _NodeOffset;        public int NodeOffset        {            get            {                return _NodeOffset;            }            set            {                _NodeOffset = value;            }        }        #endregion        #region 构造函数        public SenseTreeView()        {            //设置窗体Style            //this.SetStyle(ControlStyles.UserPaint, true);               //支持用户重绘窗体            //this.SetStyle(ControlStyles.AllPaintingInWmPaint, true);    //在内存中先绘制界面            //this.SetStyle(ControlStyles.OptimizedDoubleBuffer, true);   //双缓冲，防止绘制时抖动            //this.SetStyle(ControlStyles.DoubleBuffer, true);            //双缓冲，防止绘制时抖动             //this.UpdateStyles();            //不显示树形节点显示连接线            this.ShowLines = false;            //设置绘制TreeNode的模式            this.DrawMode = TreeViewDrawMode.OwnerDrawAll;            //不显示TreeNode前的“+”和“-”按钮            this.ShowPlusMinus = false;            //不支持CheckedBox            this.CheckBoxes = false;            //设置TreeNode的行高            SendMessage(this.Handle, TVM_SETITEMHEIGHT, 20, 0);            //设置默认BackgroundBrush            BackgroundBrush = new SolidBrush(Color.FromArgb(90, Color.FromArgb(205, 226, 252)));            //设置默认BackgroundPen            BackgroundPen = new Pen(Color.FromArgb(130, 249, 252), 1);            //设置默认NodeFont            NodeFont = new Font("宋体", 12, FontStyle.Regular);            //设置默认节点显示图标及Size            NodeExpandedImage = null;            NodeCollapseImage = null;            NodeImageSize = new Size(18, 18);            //设置默认节点显示图标便宜位置            NodeOffset = 5;        }        #endregion        #region 节点绘制函数        //绘制TreeView树中TreeNode        protected override void OnDrawNode(DrawTreeNodeEventArgs e)        {            TreeNode tn = e.Node as TreeNode;            if (tn == null)            {                return;            }            //设置Image绘制Rectangle            Point pt = new Point(tn.Bounds.X + NodeOffset, tn.Bounds.Y);            Rectangle rt = new Rectangle(pt, NodeImageSize);            if ((e.State & TreeNodeStates.Selected) != 0)            {                //绘制TreeNode选择后的背景框                e.Graphics.FillRectangle(BackgroundBrush, 2, tn.Bounds.Y, this.Width - 7, tn.Bounds.Height - 1);                //绘制TreeNode选择后的边框线条                e.Graphics.DrawRectangle(BackgroundPen, 1, tn.Bounds.Y, this.Width - 6, tn.Bounds.Height - 1);                                            }            //绘制节点图片            if (NodeExpandedImage != null && NodeCollapseImage != null)            {                if (tn.Nodes.Count != 0)                {                    if (tn.IsExpanded == true)                    {                        e.Graphics.DrawImage(NodeExpandedImage, rt);                    }                    else                    {                        e.Graphics.DrawImage(NodeCollapseImage, rt);                    }                }                rt.X += 15;            }            //绘制节点自身图片                            if (e.Node.SelectedImageIndex != -1 && this.ImageList != null)            {                rt.X += 5;                e.Graphics.DrawImage(this.ImageList.Images[e.Node.SelectedImageIndex], rt);            }            //绘制节点的文本            rt.X += 20;            rt.Y += 1;            rt.Width = this.Width - rt.X;            e.Graphics.DrawString(e.Node.Text, NodeFont, Brushes.Black, rt);        }        #endregion        #region 鼠标消息响应函数        //响应鼠标按下消息        protected override void onm ouseDown(MouseEventArgs e)        {            TreeNode clickedNode = this.GetNodeAt(e.X, e.Y);            if (clickedNode != null && NodeBounds(clickedNode).Contains(e.X, e.Y))            {                this.SelectedNode = clickedNode;                            }        }        //响应鼠标双击消息        protected override void onm ouseDoubleClick(MouseEventArgs e)        {            TreeNode clickedNode = this.GetNodeAt(e.X, e.Y);            if (clickedNode != null && NodeBounds(clickedNode).Contains(e.X, e.Y))            {                this.SelectedNode = clickedNode;                //判断节点的状态                if (clickedNode.Nodes.Count != 0)                {                    if (clickedNode.IsExpanded)                    {                        clickedNode.Collapse();                    }                    else                    {                        clickedNode.Expand();                    }                }            }        }        #endregion        #region 私有函数        //返回TreeView中TreeNode的整行区域        private Rectangle NodeBounds(TreeNode node)        {            // Set the return value to the normal node bounds.            Rectangle bounds = node.Bounds;            //if (node.Tag != null)            //{            //    // Retrieve a Graphics object from the TreeView handle            //    // and use it to calculate the display width of the tag.            //    Graphics g = this.CreateGraphics();            //    int tagWidth = (int)g.MeasureString(node.Tag.ToString(), NodeFont).Width + 6;            //    // Adjust the node bounds using the calculated value.            //    bounds.Offset(tagWidth / 2, 0);            //    bounds = Rectangle.Inflate(bounds, tagWidth / 2, 0);            //    g.Dispose();            //}            bounds.Width = this.Width;            return bounds;        }        #endregion        #region 引用函数        const int TV_FRIST = 0x1100;        const int TVM_SETITEMHEIGHT = TV_FRIST + 27;        [DllImport("user32.dll", CharSet = CharSet.Auto)]        private static extern IntPtr SendMessage(IntPtr hWnd, int nMsg, int wParam, int Param);        #endregion    }}

using System;using System.Collections.Generic;using System.ComponentModel;using System.Data;using System.Drawing;using System.Text;using System.Windows.Forms;using SenseTreeView.Properties;namespace SenseTreeView{    public partial class Form1 : Form    {        private SenseTreeView stv;        public Form1()        {            InitializeComponent();            // Create and initialize the TreeView control.            stv = new SenseTreeView();            stv.Dock = DockStyle.Left;            stv.BackColor = Color.White;            //stv.CheckBoxes = true;            stv.Width = 250;            ImageList imagelist = new ImageList();            imagelist.Images.Add(Resources._1264);            imagelist.Images.Add(Resources._1265);            imagelist.Images.Add(Resources._1268);            stv.ImageList = imagelist;            stv.NodeExpandedImage = Resources.UnSelect;            stv.NodeCollapseImage = Resources.IsSelect;            // Add nodes to the TreeView control.                        for (int x = 1; x < 4; ++x)            {                // Add a root node to the TreeView control.                                TreeNode node = new TreeNode("中华人民共和国");                node.SelectedImageIndex = 0;                for (int y = 1; y < 4; ++y)                {                    // Add a child node to the root node.                    TreeNode tn = new TreeNode("Subtask");                    tn.SelectedImageIndex = 2;                    node.Nodes.Add(tn);                }                stv.Nodes.Add(node);            }            stv.ExpandAll();            // Initialize the form and add the TreeView control to it.                        this.Controls.Add(stv);        }    }}