如何取消订阅类的 Dispose 方法中的匿名函数? [英] How to unsubscribe an anonymous function in Dispose method of a class?

问题描述

我有一个 A 类......在它的构造函数中......我正在为 Object_B 的 eventHandler 分配一个匿名函数.

I have a Class A...in it's constructor...I am assigning an anonymous function to Object_B's eventHandler.

如何从 A 类的 Dispose 方法中删除(取消订阅)它?

How do I remove (unsubscribe) that from Dispose method of class A ?

任何帮助将不胜感激！谢谢

Any help would be appreciated ! Thanks

Public Class A
{

public A()
 {

 B_Object.DataLoaded += (sender, e) =>
                {
                   Line 1
                   Line 2
                   Line 3
                   Line 4
                };
 }

Public override void Dispose()
{
  // How do I unsubscribe the above subscribed anonymous function ?
}
}

推荐答案

基本上你不能.要么将其移动到方法中，要么使用成员变量来保留委托以备后用:

You can't, basically. Either move it into a method, or use a member variable to keep the delegate for later:

public class A : IDisposable
{
    private readonly EventHandler handler;

    public A()
    {
        handler = (sender, e) =>
        {
           Line 1
           Line 2
           Line 3
           Line 4
        };

        B_Object.DataLoaded += handler;
     }

     public override void Dispose()
     {
        B_Object.DataLoaded -= handler;
     }
}

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