我正在尝试查找代码或预先打包的控件,该控件采用对象图并在TreeView中显示属性的公共属性和值(递归)。即使是一个天真的实现也没关系,我只需要一些东西开始。
解决方案必须是WPF,而不是winforms或com等......
答案 0 :(得分:23)
所以我从Chris Taylor的例子和a codeproject article的结构中获取了部分内容并将它们合并到了这里:
TreeView xaml:
<TreeView Name="tvObjectGraph" ItemsSource="{Binding FirstGeneration}" Margin="12,41,12,12" FontSize="13" FontFamily="Consolas">
<TreeView.ItemContainerStyle>
<Style TargetType="{x:Type TreeViewItem}">
<Setter Property="IsExpanded" Value="{Binding IsExpanded, Mode=TwoWay}" />
<Setter Property="IsSelected" Value="{Binding IsSelected, Mode=TwoWay}" />
<Setter Property="FontWeight" Value="Normal" />
<Style.Triggers>
<Trigger Property="IsSelected" Value="True">
<Setter Property="FontWeight" Value="Bold" />
</Trigger>
</Style.Triggers>
</Style>
</TreeView.ItemContainerStyle>
<TreeView.ItemTemplate>
<HierarchicalDataTemplate ItemsSource="{Binding Children}">
<Grid>
<Grid.ColumnDefinitions>
<ColumnDefinition />
<ColumnDefinition />
<ColumnDefinition />
</Grid.ColumnDefinitions>
<Grid.RowDefinitions>
<RowDefinition />
</Grid.RowDefinitions>
<TextBlock Text="{Binding Name}" Grid.Column="0" Grid.Row="0" Padding="2,0" />
<TextBlock Text="{Binding Type}" Grid.Column="1" Grid.Row="0" Padding="2,0" />
<TextBlock Text="{Binding Value}" Grid.Column="2" Grid.Row="0" Padding="2,0" />
</Grid>
</HierarchicalDataTemplate>
</TreeView.ItemTemplate>
</TreeView>
加电码
void DisplayObjectGraph(object graph)
{
var hierarchy = new ObjectViewModelHierarchy(graph);
tvObjectGraph.DataContext = hierarchy;
}
<强> ObjectViewModel.cs:强>
public class ObjectViewModel : INotifyPropertyChanged
{
ReadOnlyCollection<ObjectViewModel> _children;
readonly ObjectViewModel _parent;
readonly object _object;
readonly PropertyInfo _info;
readonly Type _type;
bool _isExpanded;
bool _isSelected;
public ObjectViewModel(object obj)
: this(obj, null, null)
{
}
ObjectViewModel(object obj, PropertyInfo info, ObjectViewModel parent)
{
_object = obj;
_info = info;
if (_object != null)
{
_type = obj.GetType();
if (!IsPrintableType(_type))
{
// load the _children object with an empty collection to allow the + expander to be shown
_children = new ReadOnlyCollection<ObjectViewModel>(new ObjectViewModel[] { new ObjectViewModel(null) });
}
}
_parent = parent;
}
public void LoadChildren()
{
if (_object != null)
{
// exclude value types and strings from listing child members
if (!IsPrintableType(_type))
{
// the public properties of this object are its children
var children = _type.GetProperties()
.Where(p => !p.GetIndexParameters().Any()) // exclude indexed parameters for now
.Select(p => new ObjectViewModel(p.GetValue(_object, null), p, this))
.ToList();
// if this is a collection type, add the contained items to the children
var collection = _object as IEnumerable;
if (collection != null)
{
foreach (var item in collection)
{
children.Add(new ObjectViewModel(item, null, this)); // todo: add something to view the index value
}
}
_children = new ReadOnlyCollection<ObjectViewModel>(children);
this.OnPropertyChanged("Children");
}
}
}
/// <summary>
/// Gets a value indicating if the object graph can display this type without enumerating its children
/// </summary>
static bool IsPrintableType(Type type)
{
return type != null && (
type.IsPrimitive ||
type.IsAssignableFrom(typeof(string)) ||
type.IsEnum);
}
public ObjectViewModel Parent
{
get { return _parent; }
}
public PropertyInfo Info
{
get { return _info; }
}
public ReadOnlyCollection<ObjectViewModel> Children
{
get { return _children; }
}
public string Type
{
get
{
var type = string.Empty;
if (_object != null)
{
type = string.Format("({0})", _type.Name);
}
else
{
if (_info != null)
{
type = string.Format("({0})", _info.PropertyType.Name);
}
}
return type;
}
}
public string Name
{
get
{
var name = string.Empty;
if (_info != null)
{
name = _info.Name;
}
return name;
}
}
public string Value
{
get
{
var value = string.Empty;
if (_object != null)
{
if (IsPrintableType(_type))
{
value = _object.ToString();
}
}
else
{
value = "<null>";
}
return value;
}
}
#region Presentation Members
public bool IsExpanded
{
get { return _isExpanded; }
set
{
if (_isExpanded != value)
{
_isExpanded = value;
if (_isExpanded)
{
LoadChildren();
}
this.OnPropertyChanged("IsExpanded");
}
// Expand all the way up to the root.
if (_isExpanded && _parent != null)
{
_parent.IsExpanded = true;
}
}
}
public bool IsSelected
{
get { return _isSelected; }
set
{
if (_isSelected != value)
{
_isSelected = value;
this.OnPropertyChanged("IsSelected");
}
}
}
public bool NameContains(string text)
{
if (String.IsNullOrEmpty(text) || String.IsNullOrEmpty(Name))
{
return false;
}
return Name.IndexOf(text, StringComparison.InvariantCultureIgnoreCase) > -1;
}
public bool ValueContains(string text)
{
if (String.IsNullOrEmpty(text) || String.IsNullOrEmpty(Value))
{
return false;
}
return Value.IndexOf(text, StringComparison.InvariantCultureIgnoreCase) > -1;
}
#endregion
#region INotifyPropertyChanged Members
public event PropertyChangedEventHandler PropertyChanged;
protected virtual void OnPropertyChanged(string propertyName)
{
if (this.PropertyChanged != null)
{
this.PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
}
}
#endregion
}
<强> ObjectViewModelHierarchy.cs:强>
public class ObjectViewModelHierarchy
{
readonly ReadOnlyCollection<ObjectViewModel> _firstGeneration;
readonly ObjectViewModel _rootObject;
public ObjectViewModelHierarchy(object rootObject)
{
_rootObject = new ObjectViewModel(rootObject);
_firstGeneration = new ReadOnlyCollection<ObjectViewModel>(new ObjectViewModel[] { _rootObject });
}
public ReadOnlyCollection<ObjectViewModel> FirstGeneration
{
get { return _firstGeneration; }
}
}
答案 1 :(得分:6)
嗯,这可能比你希望的更天真,但它可能会给你一个起点。它可以通过一些重构来实现,但它确实在15分钟内完成,所以把它当作它的原因,没有经过充分测试或使用任何WPF幻想。
首先是一个简单的UserControl,它只托管一个TreeView
<UserControl x:Class="ObjectBrowser.PropertyTree"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
mc:Ignorable="d"
d:DesignHeight="300" d:DesignWidth="300">
<Grid>
<TreeView Name="treeView1" TreeViewItem.Expanded="treeView1_Expanded" />
</Grid>
</UserControl>
此后面的代码只有一个名为ObjectGraph
的属性,它设置为您要浏览的对象的实例。
树只加载了第一级属性,每个节点都具有格式PropertyName:Value或PropertyName:Type,如果属性是基本类型(请参阅IsPrimitive函数),则显示该值,否则为空string被添加为子节点。添加空字符串向用户指示节点可以扩展。
当节点被扩展时,快速检查以查看第一个子节点是否为空字符串,如果是,则清除节点并将该节点的属性加载到树中。
因此,当节点扩展时,这基本上构建了树。由于两个原因,这样做更容易
1 - 无需执行递归
2 - 无需检测循环引用,这些引用会扩展到永恒或某些资源耗尽,这是永远存在的。
using System;
using System.Windows;
using System.Windows.Controls;
using System.Reflection;
namespace ObjectBrowser
{
public partial class PropertyTree : UserControl
{
public PropertyTree()
{
InitializeComponent();
}
private void treeView1_Expanded(object sender, RoutedEventArgs e)
{
TreeViewItem item = e.OriginalSource as TreeViewItem;
if (item.Items.Count == 1 && item.Items[0].ToString() == string.Empty)
{
LoadGraph(item.Items, item.Tag);
}
}
public object ObjectGraph
{
get { return (object)GetValue(ObjectGraphProperty); }
set { SetValue(ObjectGraphProperty, value); }
}
public static readonly DependencyProperty ObjectGraphProperty =
DependencyProperty.Register("ObjectGraph", typeof(object), typeof(PropertyTree),
new UIPropertyMetadata(0, OnObjectGraphPropertyChanged));
private static void OnObjectGraphPropertyChanged(DependencyObject source, DependencyPropertyChangedEventArgs e)
{
PropertyTree control = source as PropertyTree;
if (control != null)
{
control.OnObjectGraphChanged(source, EventArgs.Empty);
}
}
protected virtual void OnObjectGraphChanged(object sender, EventArgs e)
{
LoadGraph(treeView1.Items, ObjectGraph);
}
private void LoadGraph(ItemCollection nodeItems, object instance)
{
nodeItems.Clear();
if (instance == null) return;
Type instanceType = instance.GetType();
foreach (PropertyInfo pi in instanceType.GetProperties(BindingFlags.Instance | BindingFlags.Public))
{
object propertyValue =pi.GetValue(instance, null);
TreeViewItem item = new TreeViewItem();
item.Header = BuildItemText(instance, pi, propertyValue);
if (!IsPrimitive(pi) && propertyValue != null)
{
item.Items.Add(string.Empty);
item.Tag = propertyValue;
}
nodeItems.Add(item);
}
}
private string BuildItemText(object instance, PropertyInfo pi, object value)
{
string s = string.Empty;
if (value == null)
{
s = "<null>";
}
else if (IsPrimitive(pi))
{
s = value.ToString();
}
else
{
s = pi.PropertyType.Name;
}
return pi.Name + " : " + s;
}
private bool IsPrimitive(PropertyInfo pi)
{
return pi.PropertyType.IsPrimitive || typeof(string) == pi.PropertyType;
}
}
}
使用控件非常简单。在这里,我将控件放在Form上,然后将ObjectGraph设置为一个对象的实例,我随意选择了XmlDataProvider
。
<强> XAML 强>
<Window x:Class="ObjectBrowser.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="MainWindow" Height="350" Width="525" xmlns:my="clr-namespace:ObjectBrowser" Loaded="Window_Loaded">
<Grid>
<my:PropertyTree x:Name="propertyTree1" />
</Grid>
</Window>
背后的代码
using System;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
namespace ObjectBrowser
{
/// <summary>
/// Interaction logic for MainWindow.xaml
/// </summary>
public partial class MainWindow : Window
{
public MainWindow()
{
InitializeComponent();
}
private void Window_Loaded(object sender, RoutedEventArgs e)
{
var o = new XmlDataProvider();
o.Source = new Uri("http://www.stackoverflow.com");
propertyTree1.ObjectGraph = o;
}
}
}
当然,这仍然需要大量工作,对数组等类型进行特殊处理,可能是处理特殊类型的自定义视图的机制等。