check if-statement/bool when button is pressed?

Hi i have 4 buttons that all use the same function but with different gameobjects:

public void BuildShip(GameObject ship)
    {
        Instantiate(ship, mousePos, Quaternion.identity);
    }

I know how buttons work and how to call a function with them, however i want to know how to check if that certain button has been pressed. How do i see when OnClick() has been called when clicking the button? How can i use it in a if statement?

What i wanna do is: See if a certain button has been pressed, lets say button2. When button2 has been pressed i wanna for example change a int or call a debug.log etc. Im pretty sure i want to use an if-statement which is called everytime i press the button or i can have a loop to check all the time when a certain button is pressed.

But for now to simply answer this question: I want to know how to see if a button is pressed and how i can check this with the help of an if-statement.

Thanks.

with script attached to the Buttons :

public void Example(){
	switch (gameObject.name) {
	case "Button_1":
		print (gameObject.name);
		break;
	case "Button_2":
		print (gameObject.name);
		break;
	}
}