Question

I defined this multi dimensional array in C#:

int[,] values = new int[,] { { 1, 2, 3 }, { 4, 5, 6 } };

Now the values are not longer in this form but in a Dictionary:

values2.Add("KeyA", new List<float> {1,4});
values2.Add("KeyB", new List<float> {2,5});
values2.Add("KeyC", new List<float> {3,6});

Now I’m trying to parse this dictionary in the two dimensional array again, but somehow there are problems:

List<float> outList = new List<float>();
values2.TryGetValue(values2.Keys.ElementAt(0) as string, out outList);

int[,] values = new int[outList.Count, values2.Keys.Count];

for (int i = 0; i < values2.Keys.Count; i++)
{
   List<float> list = new List<float>();
   values2.TryGetValue(values2.Keys.ElementAt(i), out list);

   for (int j = 0; j < list.Count; j++)
   {
       values[i, j] = Convert.ToInt32(list.ElementAt(j));
   }
}

This throws an InnerException: System.IndexOutOfRangeException. But why? I’m not able to convert the values properly.

Edit: I can be assumed that all the values in the dictionary have the same list length. I do check this somewhere else.

Answer 1

I think it’s as simple as getting either your lengths or your indexing the wrong way round. Here’s your array creation:

int[,] values = new int[outList.Count, values.Keys.Count];

And you’re then setting values[i, j] where i is less than metrics.Keys.Count and j is less than list.Count.

You could either switch the lengths round or set values[j, i] instead. Given the original statement of the array, I suspect you want the latter approach.