Accessing variables in a structure in a class from another class with cSharp

Questions & Answers
1

I have a class called Bullet which contains a struct of bullet. How do I access variables contained in this structure, from another class using cSharp?

public class Bullet : MonoBehaviour
{
    struct bullet
    {   
            private float _shootForce;
            public float shootForce	// The force at which missiles travel 
	        {
	        	get{return _shootForce;}
	        	set{_shootForce = value;}
	        }
    }
}
4

It was a struct called Bullet before, but I wanted to put it into a class, so I named the class Bullet and the struct bullet.
I got it working now - and renamed some code. What I was missing was an instance of struct bullet(old name) in the Bullet class.

 public class Bullet
 {
    public struct bulletData
    {
         private float _shootForce;
         public float shootForce	// The force at which missiles travel 
         {
             get{return _shootForce};
             set{_shootForce = value};
         }
    }
    public bulletData playerBullet;
}

Then in another class I invoke the Bullet class with :

	Bullet B = new Bullet();

I can then access the bulletData structure by code like :

B.playerBullet.shootForce = 2f;

and

float shootForce = B.playerBullet.shootForce;
2

You have a struct called bullet, but no instance of that struct. But what are you trying to achieve by having a class called “Bullet” containing a struct called “bullet”? That’s just wrong!

3

Like jheiling said: You don’t have an instance of your struct, only a definition. A definition is just some kind of a “blueprint”. It doesn’t contain any data. You have to create an instance of that struct. It’s the same for classes. A class definition just tells the compiler how an instance of this class looks like. In Unity by dragging a class onto a GameObject you create an instance of this class. If you want the class instance have an instance of your struct, you should create one and store it in a variable. Something like that:

public class Bullet : MonoBehaviour
{
    private struct bullet
    {   
        private float _shootForce;
        public float shootForce // The force at which missiles travel 
        {
           get { return _shootForce; }
           set { _shootForce = value; }
        }
    }
    private bullet _bulletData;
    private void Awake()
    {
         _bulletData = new bullet();
    }
    private void Update()
    {
        // do something with _bulletData
    }
}

Some further notes:

  • Your struct is defined as private (private is the default visibility in C#) so you can’t use the type outside of your class.
  • If you define your struct as public you can use the struct anywhere by the full type-path. This declares a variable with the type of your struct: private Bullet.bullet myVariable;
  • Type names and method names should ALWAYS start with a capital letter. Variable names should always start lower-case. Usually properties also starts with a capital letter but some people treat them like variables.
  • You should also think about why you want to seperate some data / functions in a seperate struct and find a proper name for it. A struct “bullet” in a class “Bullet” really makes no sense. If the struct is responsible for a specific aspect of your class, find a proper name.