What properties are useful for?

Hey, I've decided to rewatch all scripting tutorials so i can understand it better.
I encountered a video about properties but it got me a little confused, What are they exactly, why to use them (There are other ways to do it. i never seen anyone use properties) and are there any example where i would put them in my game...

 

You've seen them. GameObject.transform is a property

The main advantage is that you can control visibility of your getters and setters. Have you noticed that you can't do this?

Code (csharp):

1.  
2. gameObject.transform = someOtherTransform;
3.  

You can also put logic in your getters and setters. Sometimes, a get won't even hold a value in memory but rather evaluate it and just return the result.

 

Properties are very useful.
Take a look here: https://msdn.microsoft.com/en-us/library/w86s7x04.aspx
and here: www.dotnetperls.com/property

 

In the tutorial in Unity, he shows as example Experience, now, in a game you would do the same? Like if I kill a monster I get 5 EXP, so I get the experience and in set return it with +5? Why not use just experience += 5;?
I understand better with examples on where should I use them, It seems a little confusing using them for tasks that can be achieved without the use of them...

 

Well for experience you might want to only be able to ADD experience and not subtract it, and if you subtract it, you might want experience to go no lower than the minimum experience for that level.

So you could do something like this for scenario 1:

Code (CSharp):

1. public int _experience;
2. public int Experience { get {return _experience;} set {
3.     if (value>=0) _experience += value;
4.     if (...) // levelup!
5. }
6. }

 

I'm not specifically talking about HOW to do it, I'm talking about WHY do it, I mean, why use properties in the first place? if I could just use a static int experience, then increment it whenever i want, then make a switch statement for the amount of experience thus determine the level of the player, I could basically do everything without properties, could anyone explain why to use them?

 

Didn't I do that?

The example you're giving is a bad use case (not your fault, you didn't write it after all). I'd do it this way

Code (csharp):

1.  
2. public int Experience { get; private set; }
3.  
4. public void AddExperience(int amount)
5. {
6.     Experience += amount;
7.     if (Experience > NextLevelAmount)
8.     {
9.         Experience = Experience - GetRequiredExperience(PlayerLevel);
10.         PlayerLevel++;
11.         NextLevelAmount = GetRequiredExperience(PlayerLevel);
12.     }
13. }
14.  

No other code can directly modify experience gained. You have to go through the AddExperience method which will calculate levelling and reset overflow experience as necessary. But I can still get the value to display in UI or whatever.

 

Thanks, that clears stuff out