开发VS2005下ComboBoxTreeView(下拉列表框弹出树) 与ToolStripComboBoxTreeView(下拉列表框工具条弹出树)

最进在使用VS2005开发时,发现有很多新东西,比如,我们常用的ToolBar ,MainMenu,StatusBar,变成了功能强大,样式新颖的,ToolStrip,MenuStrip,StatusStrip,等.不过还是有些不足,比如,ComboBox 变化不大,下拉框里面只能是文本的,很不方便,我的想法是在下拉ComboBox时会出现TreeView 控件,这也是我今天要做的控件ComboBoxTreeView
开始写了一个,关键点是弹出TreeView 控件,但是把TreeView 做成一个窗体,弹出,还是有什么办法,一查VS2005有一个类窗体弹出类(很强大的对象)ToolStripDropDown, 在使用此类的时候需要传递一个ToolStripControlHost类型的对象,还有个问题就是,TreeView 弹出了,会在它的上方出现了一条小白条,这个问题很棘手,不过如果你懂Win32那就一切OK了,好,我们看看这个类吧．
一：ComboBoxTreeView

 

using  System.Data;
using  System.Text;
using  System.Windows.Forms;
namespace  WindowsApplication14
{
     public   class  ComboBoxTreeView : ComboBox
     {
         private   const   int  WM_LBUTTONDOWN  =   0x201 , WM_LBUTTONDBLCLK  =   0x203 ;
        ToolStripControlHost treeViewHost;
        ToolStripDropDown dropDown;
         public  ComboBoxTreeView()
         {
            TreeView treeView  =   new  TreeView();
            treeView.AfterSelect += new  TreeViewEventHandler(treeView_AfterSelect);
            treeView.BorderStyle  =  BorderStyle.None;
           
            treeViewHost  =   new  ToolStripControlHost(treeView);
            dropDown  =   new  ToolStripDropDown();
            dropDown.Width  =   this .Width;
            dropDown.Items.Add(treeViewHost);
        }
         public   void  treeView_AfterSelect( object  sender, TreeViewEventArgs e)
         {
             this .Text = TreeView.SelectedNode.Text;
            dropDown.Close();
        }
         public  TreeView TreeView
         {
             get   {  return  treeViewHost.Control  as  TreeView; }
        }
         private   void  ShowDropDown()
         {
             if  (dropDown  !=   null )
             {
               treeViewHost.Size  = new  Size(DropDownWidth - 2 ,DropDownHeight);       
               dropDown.Show( this ,  0 ,  this .Height);
            }
        }
         protected   override   void  WndProc( ref  Message m)
         {
             if  (m.Msg  ==  WM_LBUTTONDBLCLK  ||  m.Msg  ==  WM_LBUTTONDOWN)
             {
                ShowDropDown();
                 return ;
            }         
             base .WndProc( ref  m);
        }
         protected   override   void  Dispose( bool  disposing)
         {
             if  (disposing)
             {
                 if  (dropDown  !=   null )
                 {
                    dropDown.Dispose();
                    dropDown  =   null ;
                }
            }
             base .Dispose(disposing);
        }
    }

}

附图:

二：
ToolStrip
工具条中可以插入文本，下拉框，等，如果要插入下拉树的列表框但不可以直接插入ComboBoxTreeView，必须继承上面提到的ToolStripControlHost类，

using  System;
using  System.Windows;
using  System.Windows.Forms;
using  System.ComponentModel;
using  System.Drawing;
using  System.Drawing.Design;
using  System.Windows.Forms.Design;

namespace  WindowsApplication14
{
    [DefaultProperty( " Items " )]
    [ToolStripItemDesignerAvailability(ToolStripItemDesignerAvailability.ContextMenuStrip  |  (ToolStripItemDesignerAvailability.MenuStrip  |  ToolStripItemDesignerAvailability.ToolStrip))]
     public   class  ToolStripComboBoxTreeView : ToolStripControlHost
     {
        ToolStripComboBoxTreeViewControl ToolStripComboBoxTreeViewControl #region ToolStripComboBoxTreeViewControl
        internal class ToolStripComboBoxTreeViewControl  : ComboBox
        {
            private const int WM_LBUTTONDOWN = 0x201, WM_LBUTTONDBLCLK = 0x203;
            ToolStripControlHost treeViewHost;
            ToolStripDropDown dropDown;
            private ToolStripComboBoxTreeView owner;

            public ToolStripComboBoxTreeView Owner
            {
                get
                {
                    return owner;
                }
                set
                {
                    owner = value;
                }
            }
            public ToolStripComboBoxTreeViewControl()
            {
                TreeView treeView = new TreeView();
                treeView.AfterSelect += new TreeViewEventHandler(treeView_AfterSelect);
                treeView.BorderStyle = BorderStyle.None;

                treeViewHost = new ToolStripControlHost(treeView);
                dropDown = new ToolStripDropDown();
                dropDown.Width = this.Width;
                dropDown.Items.Add(treeViewHost);
            }
            public void treeView_AfterSelect(object sender, TreeViewEventArgs e)
            {
                this.Text = TreeView.SelectedNode.Text;
                if (Owner.DropDown != null)
                {
                    Owner.DropDown(this, e);
                }
                dropDown.Close();
            }
            public TreeView TreeView
            {
                get 
                { 
                    return treeViewHost.Control as TreeView;
                }
            }
            private void ShowDropDown()
            {
                if (dropDown != null)
                {
                    treeViewHost.Size = new Size(DropDownWidth - 2, DropDownHeight);
                    dropDown.Show(this, 0, this.Height);
                }
            }
            protected override void WndProc(ref Message m)
            {
                if (m.Msg == WM_LBUTTONDBLCLK || m.Msg == WM_LBUTTONDOWN)
                {
                    ShowDropDown();
                    return;
                }
                base.WndProc(ref m);
            }
            protected override void Dispose(bool disposing)
            {
                if (disposing)
                {
                    if (dropDown != null)
                    {
                        dropDown.Dispose();
                        dropDown = null;
                    }
                }
                base.Dispose(disposing);
            }
        }
        #endregion
         public  ToolStripComboBoxTreeView()
            :  base (ToolStripComboBoxTreeView.CreateControlInstance())
         {
            ToolStripComboBoxTreeView.ToolStripComboBoxTreeViewControl control  =  
                 base .Control  as  ToolStripComboBoxTreeView.ToolStripComboBoxTreeViewControl;
                control.Owner  =   this ;
                

        }
         private   static  Control CreateControlInstance()
         {
            ComboBox comboBox  =   new  ToolStripComboBoxTreeViewControl();
             return  comboBox;
        }
        属性 属性 #region 属性
        [Browsable(false), DesignerSerializationVisibility(DesignerSerializationVisibility.Hidden)]
        public ComboBox ComboBox
        {
            get
            {
                return (base.Control as ComboBox);
            }
        }
        [Browsable(true)]
        public TreeView TreeView
        {
            get
            {
                    ToolStripComboBoxTreeView.ToolStripComboBoxTreeViewControl control = 
                base.Control as ToolStripComboBoxTreeView.ToolStripComboBoxTreeViewControl;
                    return control.TreeView;
            }
        }
        [DesignerSerializationVisibility(DesignerSerializationVisibility.Content)]
        [Editor("System.Windows.Forms.Design.ListControlStringCollectionEditor, System.Design, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a", typeof(UITypeEditor))]
        [Browsable(true)]
        [EditorBrowsable(EditorBrowsableState.Always)] 
        [Localizable(true)]
        public AutoCompleteStringCollection AutoCompleteCustomSource
        {
            get
            {
                return this.ComboBox.AutoCompleteCustomSource;
            }
            set
            {
                this.ComboBox.AutoCompleteCustomSource = value;
            }
        }
        [Browsable(false)]
        [ DesignerSerializationVisibility(DesignerSerializationVisibility.Hidden)]
        public int SelectionLength
        {
            get
            {
                return this.ComboBox.SelectionLength;
            }
            set
            {
                this.ComboBox.SelectionLength = value;
            }
        }
        [Browsable(false)]
        [DesignerSerializationVisibility(DesignerSerializationVisibility.Hidden)]
        public int SelectionStart
        {
            get
            {
                return this.ComboBox.SelectionStart;
            }
            set
            {
                this.ComboBox.SelectionStart = value;
            }
        }
        [DefaultValue(0)]
        [Localizable(true)]
        [Description("下拉框最大长度")]
        public int MaxLength
        {
            get
            {
                return this.ComboBox.MaxLength;
            }
            set
            {
                this.ComboBox.MaxLength = value;
            }
        }    
        [DefaultValue(1)]
        [RefreshProperties(RefreshProperties.Repaint)]
        public ComboBoxStyle DropDownStyle
        {
            get
            {
                return this.ComboBox.DropDownStyle;
            }
            set
            {
                this.ComboBox.DropDownStyle = value;
            }
        }
        [EditorBrowsable(EditorBrowsableState.Always)]
        [Browsable(true)]
        [DefaultValue(106)]
        public int DropDownHeight
        {
            get
            {
                return this.ComboBox.DropDownHeight;
            }
            set
            {
                this.ComboBox.DropDownHeight = value;
            }
        }
        public int DropDownWidth
        {
            get
            {
                return this.ComboBox.DropDownWidth;
            }
            set
            {
                this.ComboBox.DropDownWidth = value;
            }
        }
        #endregion
        方法 方法 #region 方法
        public void SelectAll()
        {
            ComboBox.SelectAll();
        }
        public void Select(int start, int length)
        {
            ComboBox.Select(start, length);
        }
        #endregion
        事件 事件 #region 事件
      
        public event EventHandler DropDown;
 
        #endregion
       
    }
}

附图：

客户端调用方法：
public static void Main(){
   toolStripComboBoxTreeView1.TreeView.ImageList = this.imageList1;
            TreeNode root = new TreeNode("根节点",1,2);
            root.Nodes.Add("节点1");
            root.Nodes.Add("节点2");
            root.Nodes.Add("节点3");
            root.Nodes.Add("节点4");
            root.Nodes.Add("节点5");
            root.Nodes.Add("节点6");
            toolStripComboBoxTreeView1.TreeView.Nodes.Add(root);