Question public variable vs private and Getter

Hi! What is the main reason why using private variable then use Getter instead of just public the variable?
For example:

public GameObject unit;


VS


private GameObject unit;

public GameObject GetUnit(){
return unit;
}

 

While newer to coding myself, as far as I understand the reasoning is it sets security when accessing variables from outside the script. If you have a variable that you only want to be read from outside, you can use just the get accessor.

Though the example you've shown is a method rather than a property, and generally not how they would be used. If you're specifically just wanting to return a value that's available within a script, you'd do the following:

Code (CSharp):

1. public Gameobject Unit
2. {
3.     get
4.     {
5.         return unit;
6.     {
7. }

If you want to be able to set the value as well, you'd use a 'set' accessor. The beauty of properties as well is that they don't just need to return a variable already set, but can perform any logic that you want. A simple example is using a property to check if an entity is grounded, performing a raycast inside the property.

Generally you'd use methods like in your example if you need to pass in a variable.

 

It's called Encapsulation and the gist of it is to ensure the state of the object remains valid and consistent.

 

If your variable is public than you cant see who access it.So if you will have some bug in your code what will set some wrong value to your variable then is much easier to find id with getter or setter.

 

Dinifition of encapsulation: In object-oriented programming (OOP), encapsulation refers to the bundling of data with the methods that operate on that data, or the restricting of direct access to some of an object's components.

If something should be used and changed only inside class then it should be private. Some properties should be changed only inside one class, but be read-only in others.
For example you made PlayerMovement class, and then you have MovementAnimator class which do something like:

Code (CSharp):

1. animator.SetBool("IsGrounded", movement.IsGrounded)

In that case, you can write code like this inside your Movement class:

Code (CSharp):

1. private bool _isGrounded; //for operations inside class
2. public bool IsGrounded => _isGrounded;

or like this:

Code (CSharp):

1. public bool IsGrounded { get; private set; }

The reason of all of that is to save yourself and especially other programmers (if you work in team) from mistakes.

 

thank you everyone