Arrays in Structs in C#

My structs are really messy. I'm having to use things like:

Code (csharp):

1. public struct bobStructure
2. {
3. int bob1;
4. int bob2;
5. int bob3;
6. }

when what I really want is:

Code (csharp):

1. public struct bobStructure
2. {
3. int bob[3];
4. }

Arrays in Structs don't seem to be supported. Anyone got a good work around for this??

 

int[] bob = new int[3];

Try that.

 

unfortunately not I get this error:

Assets/Scripts/map.cs(51,22): error CS0573: `map.mapStructure.bob': Structs cannot have instance field initializers

 

how about

Code (csharp):

1. fixed int bob[3];

 

Nope need to be defined as unsafe and Unity doesn't support unsafe...

Curses...

Nic.

 

Erm... just realised. Should point out this is Unity iPhone - so it's .net 1.0?? I think.

 

You can have an array in a struct, but you can only declare the size of the array at runtime. You need to declare an int[] field and then set up the array in the constructor:-

Code (csharp):

1. struct ExampleStruct {
2.     int[] ints;
3.  
4.     public ExampleStruct() {
5.         ints = new int[3];
6.     }
7. }

 

^^ That's what I was getting at! I was close.

 

Damn - I feel horrible to keep saying nope, but here's the error I get with the above example:

Code (csharp):

1. error CS0568: Structs cannot contain explicit parameterless constructors

This is the line causing the error:

Code (csharp):

1. public ExampleStruct()

 

Try this.

Code (csharp):

1. struct ExampleStruct {
2.     int[] ints;
3.  
4.     public ExampleStruct(int[] _ints) {
5.         ints = _ints;
6.     }
7. }

And to create an instance of the struct:

Code (csharp):

1.  
2. int[] ints = new int[13];
3. new ExampleStruct(ints);

 

Hi, are you using C#? I'm pretty sure C# does not allow parameterless struct constructors, so alternatively you could perhaps add a constructor with a parameter specifying the length of the array(s), or add an Initialize() function to the struct that does all the array initializing. I'm not sure if these suggestions are very ideal/efficient ways of handling it though, but they seems to work fine.

 

Some good news! The struct doesn't throw up an error. However, the instance does

Code (csharp):

1. ExampleStruct _ExampleStruct(ints);

throws up the error:

Code (csharp):

1. Identifier expected

I'm close to giving up. It seems like a crazy .net 1.0 limitation. :roll:

But I have to say thank you to all everyone for jumping in to help. It's a great example of how cool the Unity community is.

 

Here ya go. This works fine.

Code (csharp):

1. public class NewBehaviourScript : MonoBehaviour {
2.  
3.     public struct bobStructure
4.     {
5.         public bobStructure(int[] temp )
6.         {
7.             bob = temp;
8.         }
9.         public int[] bob;  
10.     }
11.  
12.     bobStructure t;
13.    
14.  
15.     void Start () {
16.         t = new bobStructure(new int[3]);
17.     }
18.    
19.     void Update () {
20.         Debug.Log(t.bob.Length);
21.     }
22. }

 

Awesome. Thank you so much guys. This is does indeed compile and work!

Now to tidy up my code!

 

Just to clarify:

Code (csharp):

1. ExampleStruct _ExampleStruct(ints);

This throws error because the syntax for instance an object it's:

type instance_name = new type(parameters);

This is how it should look like:

Code (csharp):

1. ExampleStruct _ExampleStruct = new ExampleStruct(ints);

 

Only for completeness: struct, array, constructor, prevent, prevent garbage collection

Code (CSharp):

1. using UnityEngine;
2. using System.Collections;
3.  
4. public class TestAnything : MonoBehaviour {
5.  
6.     public struct bobStructure
7.     {
8.         public bobStructure(int[] b1, int[] b2, float[] s1, string[] d1)
9.         {
10.             bob1 = b1;
11.             bob2 = b2;
12.             joe = 0;
13.             sue = s1;
14.             doe = d1;
15.         }
16.         public int[] bob1;
17.         public int[] bob2;
18.         public float joe;
19.         public float[] sue;
20.         public string[] doe;
21.     }
22.  
23.     static int maxdoe = 99;
24.     public bobStructure t = new bobStructure(new int[3], new int[3], new float[4], new string[maxdoe]);
25.  
26.     void Start () {
27.  
28.         t.joe = 0.7777777f;
29.         t.sue[3] = 39;
30.         t.doe[98] = "John";
31.  
32.         Debug.Log("t.bob1[] " + t.bob1.Length);
33.         Debug.Log("t.bob2[] " + t.bob1.Length);
34.         Debug.Log("joe " + t.joe);
35.         Debug.Log("t.sue[3] " + t.sue[3]);
36.         Debug.Log("t.doe[98] " + t.doe[98]);
37.     }
38.    
39.     void Update () {
40.     }
41. }
42.