WinForm的TreeView实现Win7 Areo效果

新建一个继承自TreeView的控件类，代码如下：

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 OnMouseDown(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 OnMouseDoubleClick(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);

        }

    }

}

效果图：

 

怎么样，效果非常库吧？