Prism 5实现:

public abstract class BindableBase : INotifyPropertyChanged
{
    public event PropertyChangedEventHandler PropertyChanged;

    protected virtual bool SetProperty<T>(ref T storage,
                                          T value,
                                          [CallerMemberName] string propertyName = null)
    {
        if (object.Equals(storage, value)) return false;

        storage = value;
        this.OnPropertyChanged(propertyName);

        return true;
    }

    protected void OnPropertyChanged(string propertyName)
    {
        var eventHandler = this.PropertyChanged;
        if (eventHandler != null)
        {
            eventHandler(this, new PropertyChangedEventArgs(propertyName));
        }
    }

    protected void OnPropertyChanged<T>(Expression<Func<T>> propertyExpression)
    {
        var propertyName = PropertySupport.ExtractPropertyName(propertyExpression);
        this.OnPropertyChanged(propertyName);
    }
}

public static class PropertySupport
{
    public static string ExtractPropertyName<T>(Expression<Func<T>> propertyExpression)
    {
        if (propertyExpression == null)
        {
            throw new ArgumentNullException("propertyExpression");
        }

        var memberExpression = propertyExpression.Body as MemberExpression;
        if (memberExpression == null)
        {
            throw new ArgumentException("The expression is not a member access expression.", "propertyExpression");
        }

        var property = memberExpression.Member as PropertyInfo;
        if (property == null)
        {
            throw new ArgumentException("The member access expression does not access a property.", "propertyExpression");
        }

        var getMethod = property.GetMethod;
        if (getMethod.IsStatic)
        {
            throw new ArgumentException("The referenced property is a static property.", "propertyExpression");
        }

        return memberExpression.Member.Name;
    }
}

这是一个Unity3D或非callermembername版本的NotifyPropertyChanged

public abstract class Bindable : MonoBehaviour, INotifyPropertyChanged
{
    private readonly Dictionary<string, object> _properties = new Dictionary<string, object>();
    private static readonly StackTrace stackTrace = new StackTrace();
    public event PropertyChangedEventHandler PropertyChanged;

    /// <summary>
    ///     Resolves a Property's name from a Lambda Expression passed in.
    /// </summary>
    /// <typeparam name="T"></typeparam>
    /// <param name="property"></param>
    /// <returns></returns>
    internal string GetPropertyName<T>(Expression<Func<T>> property)
    {
        var expression = (MemberExpression) property.Body;
        var propertyName = expression.Member.Name;

        Debug.AssertFormat(propertyName != null, "Bindable Property shouldn't be null!");
        return propertyName;
    }

    #region Notification Handlers

    /// <summary>
    ///     Notify's all other objects listening that a value has changed for nominated propertyName
    /// </summary>
    /// <param name="propertyName"></param>
    internal void NotifyOfPropertyChange(string propertyName)
    {
        OnPropertyChanged(new PropertyChangedEventArgs(propertyName));
    }

    /// <summary>
    ///     Notifies subscribers of the property change.
    /// </summary>
    /// <typeparam name="TProperty">The type of the property.</typeparam>
    /// <param name="property">The property expression.</param>
    internal void NotifyOfPropertyChange<TProperty>(Expression<Func<TProperty>> property)
    {
        var propertyName = GetPropertyName(property);
        NotifyOfPropertyChange(propertyName);
    }

    /// <summary>
    ///     Raises the <see cref="PropertyChanged" /> event directly.
    /// </summary>
    /// <param name="e">The <see cref="PropertyChangedEventArgs" /> instance containing the event data.</param>
    internal void OnPropertyChanged(PropertyChangedEventArgs e)
    {
        var handler = PropertyChanged;
        if (handler != null)
        {
            handler(this, e);
        }
    }

    #endregion

    #region Getters

    /// <summary>
    ///     Gets the value of a property
    /// </summary>
    /// <typeparam name="T"></typeparam>
    /// <param name="name"></param>
    /// <returns></returns>
    internal T Get<T>(Expression<Func<T>> property)
    {
        var propertyName = GetPropertyName(property);
        return Get<T>(GetPropertyName(property));
    }

    /// <summary>
    ///     Gets the value of a property automatically based on its caller.
    /// </summary>
    /// <typeparam name="T"></typeparam>
    /// <returns></returns>
    internal T Get<T>()
    {
        var name = stackTrace.GetFrame(1).GetMethod().Name.Substring(4); // strips the set_ from name;
        return Get<T>(name);
    }

    /// <summary>
    ///     Gets the name of a property based on a string.
    /// </summary>
    /// <typeparam name="T"></typeparam>
    /// <param name="name"></param>
    /// <returns></returns>
    internal T Get<T>(string name)
    {
        object value = null;
        if (_properties.TryGetValue(name, out value))
            return value == null ? default(T) : (T) value;
        return default(T);
    }

    #endregion

    #region Setters

    /// <summary>
    ///     Sets the value of a property whilst automatically looking up its caller name.
    /// </summary>
    /// <typeparam name="T"></typeparam>
    /// <param name="value"></param>
    internal void Set<T>(T value)
    {
        var propertyName = stackTrace.GetFrame(1).GetMethod().Name.Substring(4); // strips the set_ from name;
        Set(value, propertyName);
    }

    /// <summary>
    ///     Sets the value of a property
    /// </summary>
    /// <typeparam name="T"></typeparam>
    /// <param name="value"></param>
    /// <param name="name"></param>
    internal void Set<T>(T value, string propertyName)
    {
        Debug.Assert(propertyName != null, "name != null");
        if (Equals(value, Get<T>(propertyName)))
            return;
        _properties[propertyName] = value;
        NotifyOfPropertyChange(propertyName);
    }

    /// <summary>
    ///     Sets the value of a property based off an Expression (()=>FieldName)
    /// </summary>
    /// <typeparam name="T"></typeparam>
    /// <param name="value"></param>
    /// <param name="property"></param>
    internal void Set<T>(T value, Expression<Func<T>> property)
    {
        var propertyName = GetPropertyName(property);

        Debug.Assert(propertyName != null, "name != null");

        if (Equals(value, Get<T>(propertyName)))
            return;
        _properties[propertyName] = value;
        NotifyOfPropertyChange(propertyName);
    }

    #endregion
}

这段代码允许你像这样编写属性支持字段:

  public string Text
    {
        get { return Get<string>(); }
        set { Set(value); }
    }

此外，在resharper中，如果你创建了一个模式/搜索片段，你也可以通过将简单的道具字段转换为上面的支持来自动化你的工作流程。

搜索模式:

public $type$ $fname$ { get; set; }

替换模式:

public $type$ $fname$
{
    get { return Get<$type$>(); }
    set { Set(value); }
}

我用这种方式解决(这有点费力，但在运行时肯定更快)。

在VB中(抱歉，但我认为用c#翻译它并不难)，我用RE做了这个替换:

(?<Attr><(.*ComponentModel\.)Bindable\(True\)>)( |\r\n)*(?<Def>(Public|Private|Friend|Protected) .*Property )(?<Name>[^ ]*) As (?<Type>.*?)[ |\r\n](?![ |\r\n]*Get)

:

Private _${Name} As ${Type}\r\n${Attr}\r\n${Def}${Name} As ${Type}\r\nGet\r\nReturn _${Name}\r\nEnd Get\r\nSet (Value As ${Type})\r\nIf _${Name} <> Value Then \r\n_${Name} = Value\r\nRaiseEvent PropertyChanged(Me, New ComponentModel.PropertyChangedEventArgs("${Name}"))\r\nEnd If\r\nEnd Set\r\nEnd Property\r\n

这样转换所有代码:

<Bindable(True)>
Protected Friend Property StartDate As DateTime?

In

Private _StartDate As DateTime?
<Bindable(True)>
Protected Friend Property StartDate As DateTime?
    Get
        Return _StartDate
    End Get
    Set(Value As DateTime?)
        If _StartDate <> Value Then
            _StartDate = Value
            RaiseEvent PropertyChange(Me, New ComponentModel.PropertyChangedEventArgs("StartDate"))
        End If
    End Set
End Property

如果我想有一个更可读的代码，我可以相反，只是做下面的替换:

Private _(?<Name>.*) As (?<Type>.*)[\r\n ]*(?<Attr><(.*ComponentModel\.)Bindable\(True\)>)[\r\n ]*(?<Def>(Public|Private|Friend|Protected) .*Property )\k<Name> As \k<Type>[\r\n ]*Get[\r\n ]*Return _\k<Name>[\r\n ]*End Get[\r\n ]*Set\(Value As \k<Type>\)[\r\n ]*If _\k<Name> <> Value Then[\r\n ]*_\k<Name> = Value[\r\n ]*RaiseEvent PropertyChanged\(Me, New (.*ComponentModel\.)PropertyChangedEventArgs\("\k<Name>"\)\)[\r\n ]*End If[\r\n ]*End Set[\r\n ]*End Property

With

${Attr} ${Def} ${Name} As ${Type}

我抛出来替换set方法的IL代码，但我不能用IL编写大量编译代码…如果哪天我写了，我就说你!

虽然显然有很多方法可以做到这一点，但除了AOP的神奇答案之外，没有一种答案似乎是在没有本地字段可以引用的情况下，直接从视图模型设置Model的属性。

问题是不能引用属性。但是，您可以使用Action来设置该属性。

protected bool TrySetProperty<T>(Action<T> property, T newValue, T oldValue, [CallerMemberName] string propertyName = null)
{
    if (EqualityComparer<T>.Default.Equals(oldValue, newValue))
    {
        return false;
    }

    property(newValue);
    RaisePropertyChanged(propertyName);
    return true;
}

这可以像下面的代码摘录一样使用。

public int Prop {
    get => model.Prop;
    set => TrySetProperty(x => model.Prop = x, value, model.Prop);
}

查看这个BitBucket repo，了解该方法的完整实现，以及实现相同结果的几种不同方法，包括使用LINQ的方法和使用反射的方法。请注意，这些方法的性能较慢。

我意识到这个问题已经有无数个答案了，但没有一个适合我。我的问题是我不想有任何性能上的影响，并愿意忍受一点冗长的原因。我也不太关心自动属性，这让我想到了以下解决方案:

public abstract class AbstractObject : INotifyPropertyChanged
{
    public event PropertyChangedEventHandler PropertyChanged;

    public void OnPropertyChanged(string propertyName)
    {
        PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
    }

    protected virtual bool SetValue<TKind>(ref TKind Source, TKind NewValue, params string[] Notify)
    {
        //Set value if the new value is different from the old
        if (!Source.Equals(NewValue))
        {
            Source = NewValue;

            //Notify all applicable properties
            foreach (var i in Notify)
                OnPropertyChanged(i);

            return true;
        }

        return false;
    }

    public AbstractObject()
    {
    }
}

换句话说，如果你不介意这样做，上面的解决方案是很方便的:

public class SomeObject : AbstractObject
{
    public string AnotherProperty
    {
        get
        {
            return someProperty ? "Car" : "Plane";
        }
    }

    bool someProperty = false;
    public bool SomeProperty
    {
        get
        {
            return someProperty;
        }
        set
        {
            SetValue(ref someProperty, value, "SomeProperty", "AnotherProperty");
        }
    }

    public SomeObject() : base()
    {
    }
}

Pros

没有反映 只通知旧值!=新值 同时通知多个属性

Cons

没有自动属性(不过，您可以同时添加对两者的支持!) 一些冗长 拳击(小性能命中?)

唉，还是比这样做要好，

set
{
    if (!someProperty.Equals(value))
    {
        someProperty = value;
        OnPropertyChanged("SomeProperty");
        OnPropertyChanged("AnotherProperty");
    }
}

对于每一个单独的属性，这将成为一个额外的冗长的噩梦;-(

注意，我并不是说这个解决方案在性能上比其他解决方案更好，只是说对于那些不喜欢其他解决方案的人来说，它是一个可行的解决方案。

反射:利用反射的思想:

class ViewModelBase : INotifyPropertyChanged {

    public event PropertyChangedEventHandler PropertyChanged;

    bool Notify<T>(MethodBase mb, ref T oldValue, T newValue) {

        // Get Name of Property
        string name = mb.Name.Substring(4);

        // Detect Change
        bool changed = EqualityComparer<T>.Default.Equals(oldValue, newValue);

        // Return if no change
        if (!changed) return false;

        // Update value
        oldValue = newValue;

        // Raise Event
        if (PropertyChanged != null) {
            PropertyChanged(this, new PropertyChangedEventArgs(name));
        }//if

        // Notify caller of change
        return true;

    }//method

    string name;

    public string Name {
        get { return name; }
        set {
            Notify(MethodInfo.GetCurrentMethod(), ref this.name, value);
        }
    }//method

}//class