接口上的扩展方法;委托

不确定这里的问题是什么——您显示的代码与您引用的错误不匹配(不调用 .Disconnecting .

public interface IInterface
{
    event EventHandler Event;
    EventHandler Handler { get; set; }
}

public class Class : IInterface
{
    public event EventHandler Event;
    public EventHandler Handler { get; set; }

}

public static class InterfaceExtensions
{
    public static void DoSomething(this IInterface i)
    {
        i.Event += (o, e) => Console.WriteLine("Event raised and handled");
        i.Handler(i, new EventArgs());
    }
}

我通过以下步骤解决了这个问题:
接口外部

public delegate EventHandler<EventArgs> MyEventHandler(object sender, EventArgs e);

然后在接口内部

event EventHandler<EventArgs> Disconnecting;

变成

MyEventHandler Connected {get; set;}