wpf中TreeView的滚动条

先看效果

TreeView中是自带有滚动条的，左右滚动和上下滚动，TreeView的内部是很复杂的。

使用snoop软件可以看到，有一个上下滚动，和一个左右滚动

上下滚动

 左右滚动

1.建立一个wpf项目，文件总览 

2.xaml文件代码

"TreeView.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
        xmlns:local="clr-namespace:TreeView"
        mc:Ignorable="d"
        Title="MainWindow" Height="450" Width="800">
    
        
                
            
        
        "Red" Width="200" Height="200" HorizontalAlignment="Left">
            "verticalScrollBarForModuleTree" ViewportSize="1" FontSize="40" MinWidth="30" MinHeight="50"   Margin="0" Background="#FF10516D" Width="20" HorizontalAlignment="Right" Height="200" Foreground="#00E81212" BorderBrush="#00E01414" OpacityMask="#FFFF1818" SmallChange="10"  >
                
                    "Hidden" />
                
               
            
 
        
    

3.后台cs文件代码

using System;
using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.ComponentModel;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using System.Windows.Shapes;
 
namespace TreeView
{
    /// 
    /// MainWindow.xaml 的交互逻辑
    /// 
    public partial class MainWindow : Window
    {
        public MainWindow()
        {
            InitializeComponent();
			List persons = new List();
			Person person1 = new Person() { Name = "John DoeJohn DoeJohn Doe", Age = 42 };
			Person person2 = new Person() { Name = "Jane DoeJohn DoeJohn Doe", Age = 39 };
			Person child1 = new Person() { Name = "Sammy DoeJohn DoeJohn Doe", Age = 13 };
			person1.Children.Add(child1);
			person2.Children.Add(child1);
			person2.Children.Add(new Person() { Name = "Jenny MoeJohn Doe", Age = 17 });
			Person person3 = new Person() { Name = "Becky ToJohn DoeJohn Doe", Age = 25 };
			persons.Add(person1);
			persons.Add(person2);
			persons.Add(person3);
			persons.Add(person1);
			persons.Add(person2);
			persons.Add(person3);
			persons.Add(person1);
			persons.Add(person2);
			persons.Add(person3);
			persons.Add(person1);
			persons.Add(person2);
			persons.Add(person3);
			persons.Add(person1);
			persons.Add(person2);
			persons.Add(person3);
			person2.IsExpanded = true;
			person2.IsSelected = true;
			trvPersons.ItemsSource = persons;
		}
    }
 
    public class Person : TreeViewItemBase
	{
		public Person()
		{
			this.Children = new ObservableCollection();
		}
		public string Name { get; set; }
		public int Age { get; set; }
		public ObservableCollection Children { get; set; }
	}
 
 
	public class TreeViewItemBase : INotifyPropertyChanged
	{
		private bool isSelected;
		public bool IsSelected
		{
			get { return this.isSelected; }
			set
			{
				if (value != this.isSelected)
				{
					this.isSelected = value;
					NotifyPropertyChanged("IsSelected");
				}
			}
		}
		private bool isExpanded;
		public bool IsExpanded
		{
			get { return this.isExpanded; }
			set
			{
				if (value != this.isExpanded)
				{
					this.isExpanded = value;
					NotifyPropertyChanged("IsExpanded");
				}
			}
		}
		public event PropertyChangedEventHandler PropertyChanged;
		public void NotifyPropertyChanged(string propName)
		{
			if (this.PropertyChanged != null)
				this.PropertyChanged(this, new PropertyChangedEventArgs(propName));
		}
	}
}

4.ScrollViewer.xaml样式文件

"http://schemas.microsoft.com/winfx/2006/xaml/presentation"
                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
    
    
    
    
    
    
 
    
    
    
    
    
 
    
    
 
    
    

5.配置App.xaml

"TreeView.App"
             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
             xmlns:local="clr-namespace:TreeView"
             StartupUri="MainWindow.xaml">
    
        
            
                "pack://application:,,,/TreeView;component/ScrollViewer.xaml"/>
            
        
    

 6.效果

拓展

展开和收缩功能，直接传递TreeView控件和true或者false

	private void SetNodeExpandedState(ItemsControl control, bool expandNode)
		{
			try
			{
				if (control != null)
				{
					foreach (object item in control.Items)
					{
						TreeViewItem treeItem = control.ItemContainerGenerator.ContainerFromItem(item) as TreeViewItem;
 
						if (treeItem != null && treeItem.HasItems)
						{
							treeItem.IsExpanded = expandNode;
 
							if (treeItem.ItemContainerGenerator.Status != System.Windows.Controls.Primitives.GeneratorStatus.ContainersGenerated)
							{
								treeItem.UpdateLayout();
							}
 
							SetNodeExpandedState(treeItem as ItemsControl, expandNode);
						}
					}
				}
			}
			catch (Exception ex)
			{
				
			}
		}

上面操作是某一个界面使用的

如果需要全局引用，去掉界面上面的代码

打开ScrollViewer.xaml的代码即可