Adding a function as an object's property-CodePudding

In my project I'm implementing an action class and was wondering if it was possible to pass a function as a parameter like this:

public class Action : MonoBehavior {
  public int ID;
  public string Name;
  //Test variable to store a function here
}

Where later I would create a function, such as this one, and call it.

void TestFunction() {
  print("Test");
}
public Action ExampleAction;
ExampleAction.Test = TestFunction();

And then finally I could simply call "Action.Test" to run TestFunction.

I've done some research on the topic and I believe it's somewhat related to delegation but how could I do it in this scenario?

And even more, is this sort of implementation reliable or the nicest way to do it? In my project I plan on having a lot of toggleable actions, that when clicked, will continuously do a large variety of different things.

CodePudding user response：

The name Action is actually already used to represent a specific type of delegate, so I would recommend renaming your Action class to something more specific and then leverage the built-in Action type for your Test property.

public class ActionMonoBehavior : MonoBehavior {
  public int ID;
  public string Name;
  public Action Test;
}

public ActionMonoBehavior ExampleAction = new ActionMonoBehavior
{
  ID = 1,
  Name = "Example"
  Test = TestFunction // or () => TestFunction()
};

ExampleAction.Test(); // or ExampleAction.Test.Invoke();

CodePudding user response：

To my understanding, what you are trying to do is create a parameterized delegate.

I think UnityAction fit this perfectly. UnityAction is a built-in delegate that takes no parameters and returns no value.

In your case, you would want to use a parameterized UnityAction<T1, T2>, where you would set T1 to int and T2 to string.

Here is a snippet for demonstration:

using UnityEngine;
using UnityEngine.Events;

public class UnityActionDemo
{
    UnityAction<int, string> action;
    private void Start()
    {
        action = TestMethod;
    }

    public void TestMethod(int id, string name)
    {
        Debug.Log("id is: "   id   "\t name is: "   name);
    }
}

action can then be passed around to any method that takes a UnityAction<int, string> as a parameter.

In order to invoke the method, call action.Invoke with the parameters you'd like to use:

action.Invoke(27, "A cool method name");