Question

I have a program that will need to run different methods depending on what I want it to talk to, and I want to know if there is a way to store some sort of method pointer or something of that sort in an array. So I want an array where each element would be something like this:

[Boolean: Do_this?] [Function_pointer] [Data to pass to the function]

So basically, I can put this into a for loop and not call each function individually. Another block of code would fill in the Boolean of whether to run this function or not, and then my for loop would go through and run the function with its appropriate data if the Boolean is true.

I know delegates are similar to function pointers, but if that is the answer here, I’m not entirely sure how I would construct what I want to construct.

Is this possible in C#?

Answer 1

You could declare a specific object type to hold in a delegate, a flag that indicates whether to do that or now and the data. Note that what you are describing is very similar to events as they are also defined by a callback and some event data.

The skeletal model would look something like this, assuming all methods you want to call have the same signature (you can work around that, if you need a whole bunch of various signatures by using reflection):

// This reflects the signature of the methods you want to call
delegate void theFunction(ActionData data);

class ActionData
{
    // put whatever data you would want to pass
    // to the functions in this wrapper
}

class Action
{
    public Action(theFunction action, ActionData data, bool doIt)
    {
        this.action = action;
        this.data = data;
        this.doIt = doIt;
    }

    public bool doIt
    {
        get;
        set;
    }

    public ActionData data
    {
        get;
        set;
    }

    public theFunction action
    {
        get;
        set;
    }

    public void run()
    {
        if (doIt)
            action(data);
    }
}

And a regular use case would look something like this:

class Program
{
    static void someMethod(ActionData data)
    {
        Console.WriteLine("SUP");
    }

    static void Main(string[] args)
    {
        Action[] actions = new Action[] {
            new Action(Program.someMethod, new ActionData(), true)
        };

        foreach(Action a in actions) 
            a.run();
    }
}