Is there a way in C# to call a method just once like in the jQuery "one" method?

Question

I wish to know if there is a way to execute code in C# just once, like "one" in jquery:

$("#foo").one("click", function() { alert("This will be displayed only once."); });

What I would like to do is the following:

public void foo(){
  Console.Write("hello");
}

then

foo();
foo();
foo();

and the output result must be

hello

I´m looking for a library and not just using flags attributes.

Answer 1

I know this is old news... but here is a Functional approach to the question that someone might find useful:

    public static Action<T> Once<T>(Action<T> action )
    {
        return (arg) =>
        {
            action?.Invoke(arg);
            action = null;
        };
    }

Then you can generate a function that will only do the meat of the work one time:

    var writeNumberToConsole = Once<int>( Console.WriteLine );
    writeNumberToConsole(1); // "1"
    writeNumberToConsole(2); -> //nothing
    writeNumberToConsole(3); -> //nothing

Answer 2

I can't imagine why do something like that, but if you really do it and if you want it universal for any method, you can do this:

void Main() {
    var myFoo = callOnlyOnce(foo);
    myFoo();
    myFoo();
    myFoo();

   var myBar = callOnlyOnce(bar);
   myBar();
   myBar();
   myBar();
}

void foo(){
  Console.Write("hello");
}
void bar() { Console.Write("world"); }


Action callOnlyOnce(Action action){
    var context = new ContextCallOnlyOnce();
    Action ret = ()=>{
        if(false == context.AlreadyCalled){
            action();
            context.AlreadyCalled = true;
        }
    };

    return ret;
}
class ContextCallOnlyOnce{
    public bool AlreadyCalled;
}