我知道这是一个老问题，最初的问题已在 .NET 4 中解决。老实说，这有点偏离主题。
在我想在 MVVM 中使用 RadioButtons 的大多数情况下，它是在 enum 的元素之间进行选择，这需要将 VM 空间中的 bool 属性绑定到每个按钮并使用它们来设置反映实际选择的整体 enum 属性，这很快就会变得非常乏味。所以我想出了一个可重复使用且非常易于实施且不需要 ValueConverters 的解决方案。
View 几乎相同，但是一旦你的 enum 就位，VM 端就可以使用单个属性来完成。
主窗口虚拟机
using System.ComponentModel;
namespace EnumSelectorTest
{
public class MainWindowVM : INotifyPropertyChanged
{
public EnumSelectorVM Selector { get; set; }
private string _colorName;
public string ColorName
{
get { return _colorName; }
set
{
if (_colorName == value) return;
_colorName = value;
RaisePropertyChanged("ColorName");
}
}
public MainWindowVM()
{
Selector = new EnumSelectorVM
(
typeof(MyColors),
MyColors.Red,
false,
val => ColorName = "The color is " + ((MyColors)val).ToString()
);
}
public event PropertyChangedEventHandler PropertyChanged;
protected virtual void RaisePropertyChanged(string propertyName)
{
PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
}
}
}
完成所有工作的类继承自 DynamicObject。从外部看，它为 enum 中的每个元素创建一个 bool 属性，前缀为“Is”、“IsRed”、“IsBlue”等，可以绑定到 from XAML。以及保存实际 enum 值的 Value 属性。
public enum MyColors
{
Red,
Magenta,
Green,
Cyan,
Blue,
Yellow
}
EnumSelectorVM
using System;
using System.ComponentModel;
using System.Dynamic;
using System.Linq;
namespace EnumSelectorTest
{
public class EnumSelectorVM : DynamicObject, INotifyPropertyChanged
{
//------------------------------------------------------------------------------------------------------------------------------------------
#region Fields
private readonly Action<object> _action;
private readonly Type _enumType;
private readonly string[] _enumNames;
private readonly bool _notifyAll;
#endregion Fields
//------------------------------------------------------------------------------------------------------------------------------------------
#region Properties
private object _value;
public object Value
{
get { return _value; }
set
{
if (_value == value) return;
_value = value;
RaisePropertyChanged("Value");
_action?.Invoke(_value);
}
}
#endregion Properties
//------------------------------------------------------------------------------------------------------------------------------------------
#region Constructor
public EnumSelectorVM(Type enumType, object initialValue, bool notifyAll = false, Action<object> action = null)
{
if (!enumType.IsEnum)
throw new ArgumentException("enumType must be of Type: Enum");
_enumType = enumType;
_enumNames = enumType.GetEnumNames();
_notifyAll = notifyAll;
_action = action;
//do last so notification fires and action is executed
Value = initialValue;
}
#endregion Constructor
//------------------------------------------------------------------------------------------------------------------------------------------
#region Methods
//---------------------------------------------------------------------
#region Public Methods
public override bool TryGetMember(GetMemberBinder binder, out object result)
{
string elementName;
if (!TryGetEnumElemntName(binder.Name, out elementName))
{
result = null;
return false;
}
try
{
result = Value.Equals(Enum.Parse(_enumType, elementName));
}
catch (Exception ex) when (ex is ArgumentNullException || ex is ArgumentException || ex is OverflowException)
{
result = null;
return false;
}
return true;
}
public override bool TrySetMember(SetMemberBinder binder, object newValue)
{
if (!(newValue is bool))
return false;
string elementName;
if (!TryGetEnumElemntName(binder.Name, out elementName))
return false;
try
{
if((bool) newValue)
Value = Enum.Parse(_enumType, elementName);
}
catch (Exception ex) when (ex is ArgumentNullException || ex is ArgumentException || ex is OverflowException)
{
return false;
}
if (_notifyAll)
foreach (var name in _enumNames)
RaisePropertyChanged("Is" + name);
else
RaisePropertyChanged("Is" + elementName);
return true;
}
#endregion Public Methods
//---------------------------------------------------------------------
#region Private Methods
private bool TryGetEnumElemntName(string bindingName, out string elementName)
{
elementName = "";
if (bindingName.IndexOf("Is", StringComparison.Ordinal) != 0)
return false;
var name = bindingName.Remove(0, 2); // remove first 2 chars "Is"
if (!_enumNames.Contains(name))
return false;
elementName = name;
return true;
}
#endregion Private Methods
#endregion Methods
//------------------------------------------------------------------------------------------------------------------------------------------
#region Events
public event PropertyChangedEventHandler PropertyChanged;
protected virtual void RaisePropertyChanged(string propertyName)
{
PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
}
#endregion Events
}
}
要响应更改，您可以订阅 NotifyPropertyChanged 事件或将匿名方法传递给构造函数，如上所述。
最后是 MainWindow.xaml
<Window x:Class="EnumSelectorTest.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"
mc:Ignorable="d"
Title="MainWindow" Height="350" Width="525">
<Grid>
<StackPanel>
<RadioButton IsChecked="{Binding Selector.IsRed}">Red</RadioButton>
<RadioButton IsChecked="{Binding Selector.IsMagenta}">Magenta</RadioButton>
<RadioButton IsChecked="{Binding Selector.IsBlue}">Blue</RadioButton>
<RadioButton IsChecked="{Binding Selector.IsCyan}">Cyan</RadioButton>
<RadioButton IsChecked="{Binding Selector.IsGreen}">Green</RadioButton>
<RadioButton IsChecked="{Binding Selector.IsYellow}">Yellow</RadioButton>
<TextBlock Text="{Binding ColorName}"/>
</StackPanel>
</Grid>
</Window>
希望其他人觉得这很有用，因为我认为这些会在我的工具箱中。