Initalizing Arrays with Variable Length

I would like to create an array whose length can be changed per a variable. It will not let me initialize the array using the variable's length.

This is somewhat of an demonstration of what I would like:

Code (CSharp):

1. public int max_slots;
2. public int[][,] inventory = new int[max_slots][,];

It says that I can't use a non-static variable in this way. Is there some way around this?

 

make it static?

Code (csharp):

1.  
2. static public int max_slots = 10;
3. public int[][,] inventory = new int[max_slots][,];
4.  

or, if you want it to be non-static (to edit in inspector), init your array in OnEnable

 

Thank you!