Unity3D calling my own classes - unity3d

Question

So I have a file with all my classes in it:
using UnityEngine;
using System.Collections;
public class Touch {
public int DoSomthing(int _test) {
int bla = _test + 1;
return bla;
}
}
public class Swipe {
}
public class Zoom {
}
How can I make it so that I can acces them in all my other scripts just like the transform class?
So I would like to acces touch like this in any other script:
int blabla = Toch.DoSomthing(5);
Without constructing the class.

Answer 1

Whenever you want to access class (if it's not static) you need to specify what instance of that class you want to access, if you attach your script to the main camera you can access it like this:
Toch someNameOfVar = Camera.main.gameObject.GetComponent<Toch>();
int blabla = someNameOfVar.DoSomething(5);
You create a new variable that has the type of the class you are accessing and then get the reference to specific instance of that class by specifying on what gameObject it is.
But, there is something called static class and static methods. You can change your script to this:
public class Touch : MonoBehaviour {
public static int DoSomthing(int _test){
int bla = _test + 1;
return bla;
}
}
This way you can access it without specifying which instance of it you want.
You can learn more about statics here : https://unity3d.com/learn/tutorials/modules/intermediate/scripting/statics

Answer 2

You make those methods static, and just call them.
public static int DoSomthing(int _test)
{
int bla = _test + 1;
return bla;
}
And then call them Touch.DoSomthing(1). It may require using on top, if you have them in another namespace.

Answer 3

First make DoSomthing static like this because you want to access DoSomthing by class not by instance.
public static int DoSomthing(int _test)
{
int bla = _test + 1;
return bla;
}
and if you want to apply any class on gameobject as a component make it derive from MonoBehaviour. Like if you want to attach Touch script to a game object then do this
public class Touch : MonoBehaviour {
}