确定 setter 中的调用者 - 或设置属性，静默 [英] Determining the caller inside a setter -- or setting properties, silently

问题描述

给定一个标准的视图模型实现，当一个属性发生变化时，有没有办法确定变化的发起者?换句话说，在下面的视图模型中，我希望PropertyChanged"事件的sender"参数是调用 Prop1 setter 的实际对象:

Given a standard view model implementation, when a property changes, is there any way to determine the originator of the change? In other words, in the following view model, I would like the "sender" argument of the "PropertyChanged" event to be the actual object that called the Prop1 setter:

public class ViewModel : INotifyPropertyChanged
{
    public double Prop1
    {
        get { return _prop1; }
        set
        {
            if (_prop1 == value)
                return;
            _prop1 = value;

            // here, can I determine the sender?
            RaisePropertyChanged(propertyName: "Prop1", sender: this);
        }
    }
    private double _prop1;

    // TODO implement INotifyPropertyChanged
}

或者，是否可以将 CallerMemberNameAttribute 应用于属性设置器?

Alternatively, is it possible to apply CallerMemberNameAttribute to a property setter?

推荐答案

如果我理解正确，您是在询问 setter 的调用者.这意味着，在到达 setter 本身之前，调用堆栈中的前一个方法调用(这也是一个方法).

If I understood correctly, you're asking about the caller of the setter. That means, the previous method call in the call stack before getting to the setter itself (which is a method too).

为此使用 StackTrace.GetFrames 方法.例如(取自 http://www.csharp-examples.net/reflection-callstack/):

Use StackTrace.GetFrames method for this. For example (taken from http://www.csharp-examples.net/reflection-callstack/):

using System.Diagnostics;

[STAThread]
public static void Main()
{
  StackTrace stackTrace = new StackTrace();           // get call stack
  StackFrame[] stackFrames = stackTrace.GetFrames();  // get method calls (frames)

  // write call stack method names
  foreach (StackFrame stackFrame in stackFrames)
  {
    Console.WriteLine(stackFrame.GetMethod().Name);   // write method name
  }
}

输出:

Main
nExecuteAssembly
ExecuteAssembly
RunUsersAssembly
ThreadStart_Context
Run
ThreadStart

基本上，您要的是 stackFrames[1].GetMethod().Name.

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