Multi-dimensional arrays

I'm trying to declare a 3 dimensional array in C#, and I'm having some errors thrown at me. This line is the culprit:

Code (csharp):

1. public int[] 3dArray = new int[ , , ];

this gives me the error "new expression required () or [] after type. So if I change it to:

Code (csharp):

1. public int[] 3dArray = new int[3];

and I get the error "incorrect number of indexes for array. expected 1 got 3"

What's the correct way to declare multidimensional arrays in C# (and JS while I'm at it)?

 

thanks Joachim, it works if I explicitly define my array's dimensions, but what if I want my array to have a dynamic size based on the variables in the script? When working in C# in windows apps, the declaration

Code (csharp):

1. int[ , , ] myArray = new int[]

works just fine, but Unity yells at me. Am I forced to declare my array's dimensions when I instantiate it?

 

On C# you can do this for a 3 dimensional array:

Code (csharp):

1. int[,,] myArray = new int[,,]{}

the part of the {} is the initializer, giving the initial values, and if you have to set the values it could be something like this:

Code (csharp):

1. int[ , , ] myArray = new int[]{{{1,2},{3,4},{5,6}},{{7,8},{9,10},{11,12}},{{13,14},{15,16},{17,18}}

This type of arrays are fixed arrays, you would have to have arrays defined as items on other arrays:

Code (csharp):

1. ArrayList firstDimension = new ArrayList();
2. ArrayList secondDimensionChild = new ArrayList();
3. ArrayList thirdDimensionChild = new ArrayList();
4. firstDimension.Add(secondDimensionChild);
5. secondDimensionChild.Add(thirdDimensionChild);
6. thirdDimensionChild.Add(3);

Then yo can access them through the ArraList's indexer (indexing 0 based):

Code (csharp):

1. int value = (int)firstDimension[0][0][0];

 

I'm not sure if this is the most efficient way or if this has some artifacts that I haven't noticed, but what I found is that Unity doesn't mind declaring multiple dimension arrays

Code (CSharp):

1. void initDungeonPoints(){
2.         voxelPoints = new float[xCount][][];//sets up the array with an x size of [xCount]
3.         // loops through the 3D array and sets the value for the first dimension to
4.         // a 2d array with the "x" dimension that is acting as the 3D array's
5.         // y set to the y size of [ySize]
6.         for (int x = xCount-1; x>=0; x--){
7.             voxelPoints[x] = new float[yCount][];
8.             // loops through the 2D array and sets the value of the first dimension of the
9.             // 2D array to a 1D array of size [zCount]
10.             for (int y = yCount-1; y>=0; y--){
11.                 voxelPoints[x][y] = new float[zCount];
12.                 //loops through the final array and sets all of the points to a float value of 1
13.                 for (int z = zCount-1; z>=0; z--){
14.                     voxelPoints[x][y][z] = 1f;
15.                 }
16.             }
17.         }
18.     }

This might not work in previous versions of Unity, but it seems stable enough for my purposes.

 

What you have there is not a multi-dimensional array. It is a one-dimensional array of one-dimensional arrays of one-dimensional arrays. You could still use it to store the same data, but It's not exactly the same thing.