如何将委托传递给非静态委托的方法？ [英] How pass delegate to a method, where delegates are non static?

问题描述

我才刚刚开始理解代表，我有一个实现IDisposable的类：

I'm just beginning understanding delegates, I have a class that implemens IDisposable:

public class MyClass : IDisposable
{
  public delegate int DoSomething();

  public int Zero() {return 0;}
  public int One() {return 1;}

  public void Dispose()
  {
    // Cleanup
  }
}

一种方法（已定义在另一个使用MyClass的类中）：

A method (defined in an another class) that is using MyClass:

public class AnotherCLass
{
    public static void UseMyClass(MyClass.DoSomething func)
    {
      using (var mc = new MyClass())
      {
        // Call the delegate function
        mc.func(); // <-------- this is what i should actually call
      }
    }
}

实际的问题：如何将Zero（）函数传递给UseMyClass方法？我是否必须创建MyClass的实例（我想避免这种情况...）？

public static void main(string[] args)
{
  // Call AnotherClass method, by passing Zero()
  // or One() but without instatiate MyCLass
  AnotherClass.UseMyClass(??????????);
}

推荐答案

由于是实例方法，如果要调用它，则需要一个实例。这就是CLR的工作原理。但是，可以使用两种选择：

Because it's an instance method, if you want to call it, you need an instance. That's simply how the CLR works. However, there are two options you could go with:

• 使成员函数保持静态。就像返回静态值一样简单，没有理由让它们成为实例方法。但是，如果确实需要实例数据...


• 使用单例实例。这样，您不必每次都创建一个新实例。想要调用您的静态方法。

• Make the member functions static. If they're as simple as returning a static value, there's no reason for them to be instance methods. However, if you do actually require instance data...
• Use a singleton instance. This way you don't need to create a new instance every time you want to call your static method.

您可以这样操作：

public class MyClass
{
    private static MyClass singletonInstance;
    public static MyClass SingletonInstance
    {
        get
        {
            if (singletonInstance == null)
            {
                singletonInstance = new MyClass();
            }
            return singletonInstance;
        }
    }

    // the rest of your class implementation
}

然后，您可以像这样调用静态方法：

Then, you can call your static method like so:

AnotherClass.UseMyClass(MyClass.SingletonInstance.Zero);

这篇关于如何将委托传递给非静态委托的方法？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！