是否可以使用类似于自动属性 ({ get; set; }) 的语法来声明引发 PropertyChanged 事件的属性？

Question

I'm wondering how to simplify the use of properties when they must raise the PropertyChanged event. I mean as soon as you need to raise the event, the setter must do it, hence the property cannot be an auto-property. This causes some complication of the code, especially when there are multiple properties concerned, for no other purpose than to simply raise the event:

protected FlowDocument document;
protected bool hyphenation = true;
protected bool optimalParagraphs = true;

public event PropertyChangedEventHandler PropertyChanged;

public FlowDocument Document { get => document; set { document = value; RaisePropertyChanged (); } }
public bool Hyphenation { get => hyphenation; set { hyphenation = value; RaisePropertyChanged (); } }
public bool OptimalParagraphs { get => optimalParagraphs; set { optimalParagraphs = value; RaisePropertyChanged (); } }

// Raise event
protected void RaisePropertyChanged ([CallerMemberName] string propertyName = null) {
    PropertyChanged?.Invoke (this, new PropertyChangedEventArgs (propertyName));
}

The complication is within this part which is repeated for each property:

protected FlowDocument document;
public FlowDocument Document { get => document; set { document = value; RaisePropertyChanged (); } }

because there is no possibility to express it like:

public FlowDocument Document { get; setAndRaiseEvent; }

A search on the site proposes this similar, but not duplicate, question:

• Is it possible to use attributes to automatically raise an event on a property change

With current C# possibilities, is there a way to simplify the original code? (I'm enlarging the scope to any possibility).

Answer 1

"With current C# possibilities"? No.

But if you install the Fody and PropertyChanged.Fody NuGet packages and add a file named "FodyWeavers.xml" with the following contents to your project:

<Weavers>
    <PropertyChanged />
</Weavers>

... Fody will inject code that raises the PropertyChanged event into all property setters of all classes that implement INotifyPropertyChanged when you build the project.

Please refer to GitHub for more information.