For a 3D array you want your JSON in this format:
{
"c2array":true,
"size":[2,3,4],
"data":[
[ [0,1,2,3], [4,5,6,7], [8,9,10,11] ],
[
[12,13,14,15], [16,17,18,19 ], [20,21,22,23] ]
]
}
For 2D like this:
{
"c2array":true,
"size":[2,3,1],
"data":[
[ [0], [1], [2] ],
[
[3], [4], [5] ]
]
}