c# - 事件默认初始化器

Question

我曾经使用以下内容:

public event EventHandler OnComplete = delegate { };

我不确定，这是怎么称呼的，这是“事件默认初始化程序”吗？？

但问题似乎出在我派生自 EventArgs、创建我自己的 EventHandler 并决定使用相同的方法时。请参阅:

public class MyEventArgs : EventArgs
{
    int result;
    public int Result
    {
        get
        {
            if (exceptionObject == null)
                return result;
            else
                throw new InvalidOperationException();
        }
        internal set { result = value; }
    }

    Exception exceptionObject;
    public Exception ExceptionObject
    {
        get { return exceptionObject; }
        internal set { exceptionObject = value; }
    }
}

public delegate EventHandler MyEventHandler(object sender, MyEventArgs e);

public class MyOperation
{
    public event MyEventHandler OnOperationComplete = delegate { };
}

所以，这条线

public event MyEventHandler OnOperationComplete = delegate { };

导致问题。

如何为“我的”事件进行正确的默认初始化？

Answer 1

public event MyEventHandler OnOperationComplete = (sender, args) => { return null; };

我还认为你的意思是:

public delegate void MyEventHandler(object sender, MyEventArgs e);

不是

public delegate EventHandler MyEventHandler(object sender, MyEventArgs e);