委托问题，在调用时 [英] delegate problem, when invoking it

问题描述

大家好.
请帮帮我.

在工作期间，我想委托一个方法.

这是类Publisher

Hello all.
Please help me.

During my work, i want to delegate a method,.

This is class Publisher

public delegate void SaveAppontment(DateTime date, String s)
            SaveAppointment sv =null;
            if (sv != null)
            {
                sv.Invoke(DateTime.Now, "");
            }

----------------------

我想从其他班级开始..

B类
========
在这里，我想在上面的委托中发送执行此工作的方法.
Publisher.SaveAppontment sd = method(date，s)//或其他什么东西，在这里我不在乎，我在乎发布者类，如果我使用的是正确的委托人！

----------------------

From my other Class, i want to do this..

CLASS B
========
Here i want to send the method that does the job in my delegate above.
Publisher.SaveAppontment sd = method(date, s)// or something,, i dont care here a lot, i care in the publisher class, if i using the delegtes right !!?


Is it possible ??

推荐答案

首先，您可以在开头使用sv = null，这意味着它将始终为null！这意味着将永远不会执行sv.Invoke(DateTime.Now, "");.我对你在做什么感到有些困惑.这是使用委托的方法:

First of all you have sv= null at the beginning, which means it will always be null! which means sv.Invoke(DateTime.Now, ""); will never be executed. I am a little confused about what you are doing. Here is how to use a delegate:

public delegate void SaveAppointmentDelegate(DateTime dt, string s);

public SaveAppointmentDelegate SaveAppointment;

public void FireSaveAppointmentEvent(DateTime dt, string s)
{
    if (SaveAppointment != null) SaveAppointment(dt,s);
}

您可以通过以下方式将处理程序添加到SaveAppointment:

You add a handler to the SaveAppointment by the following:

SaveAppointment += SaveAppointmentEventHandler;

这篇关于委托问题，在调用时的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！