动态事件订阅和取消订阅C＃事件 [英] Dynamic event subscribe and unsubscribe to a C# event

问题描述

如何在Windows窗体应用程序中动态订阅和取消订阅C＃事件。因此，给定一个Object实例和一个包含事件名称的String名称，您订阅该事件并在该事件被触发时执行某些操作？



我尝试过：



string _EventHandler = string.Empty;



_EventHandler = cntrl + @。 + _EventName;





_EventHandler + = new EventHandler（SaveData）;



private void SaveData（object sender，EventArgs e）

{

//做某事

}

How to dynamically subscribe and unsubscribe to a C# event in windows Forms Application. so that given a Object instance and a String name containing the name of the event, you subscribe to that event and do something when that event has been fired?

What I have tried:

string _EventHandler = string.Empty;

_EventHandler = cntrl + @"." + _EventName;


_EventHandler += new EventHandler(SaveData);

private void SaveData(object sender, EventArgs e)
{
// doing something
}

推荐答案

不太难......只是凌乱，因为你需要玩耍。试试这个：

Not too difficult ... just messy, because you need to play around. Try this:

private void AddHandler(Control c, string eventName, EventHandler handler)
    {
    Type t = c.GetType();
    EventInfo ei = t.GetEvent(eventName);
    ei.AddEventHandler(c, handler);
    }

但我希望你有充分的理由，因为它不会提高你的代码可读性......

But I hope you have a good reason, because it's not going to improve your code readability...

你好我得到解决方案的是我的代码



//订阅事件以调用其他类方法的代码

//添加方法的代码在控件事件的另一个类中

//这里_EventName是事件的名称（Click，Enter，Leave等..）

//在MyEventsHandler类我有一个SaveData方法



EventHandler eHandler = new EventHandler（MyEventsHandler.SaveData）;

AddHandler（cntrl，_EventName，eHandler）;





//添加Eventhandler的函数

private void AddHandler（Control c，string eventName，EventHandler handler）

{

尝试

{

类型t = c.GetType（）;

EventInfo ei = t.GetEvent（eventName）;

ei.RemoveEventHandler（c，handler）;

ei.AddEventHandler（c，handler）;

}

catch（exception ex）

{

MessageBox.Show（System.Reflection.MethodInfo.GetCurrentMethod（）。Name ++ ex.Message，

错误， MessageBoxButtons.OK，MessageBoxIcon.Error）;

}

}

Hi I got the solution here is my code

// Code for subscribing an event to call other class method
// code for adding a method in another class to the control event
// here _EventName is the name of the event (Click, Enter, Leave etc..)
// In MyEventsHandler class I have a SaveData method

EventHandler eHandler = new EventHandler(MyEventsHandler.SaveData);
AddHandler(cntrl, _EventName, eHandler);


//Function to add Eventhandler
private void AddHandler(Control c, string eventName, EventHandler handler)
{
try
{
Type t = c.GetType();
EventInfo ei = t.GetEvent(eventName);
ei.RemoveEventHandler(c, handler);
ei.AddEventHandler(c, handler);
}
catch (Exception ex)
{
MessageBox.Show(System.Reflection.MethodInfo.GetCurrentMethod().Name + " " + ex.Message,
"Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
}
}

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