trying to understand all this syntax

Question

public class TwoDimensions
{
static void Main()
{
int[,] twodim = new int[,] { { 1, 2, 3 }, { 9, 8, 7 } };

int dim1 = twodim.GetLength(0);
int dim2 = twodim.GetLength(1);

WriteLine("Dimension 0 contains {0} elements.", dim1);
WriteLine("Dimension 1 contains {0} elements.\n", dim2);

for (int i1=0; i1 < dim1; i1++)
{
for (int i2=0; i2 < dim2; i2++)
{
WriteLine("twodim[{0},{1}] = {2}", i1, i2, twodim[i1,i2]);
}
}
ReadLine();

This is my for loop code for a C# project I am learning in a tutorial. What does is the below code doing? I understand everything else. Thanks for help.

WriteLine("twodim[{0},{1}] = {2}", i1, i2, twodim[i1,i2]);

Answer 1

WriteLine("twodim[{0},{1}] = {2}", i1, i2, twodim[i1,i2]);
that line is for printing the values of the twodim array.
the number that are inside {} are like place holders for the values in the order they appear after the " ".
it's a way of displaying variables inside of strings without using + sign.
{0} holds the value of i1
{1} holds the value of i2
{2} holds the value of twodim[i1, i2]
if you change the order of variables they will show in different places.
ex:
WriteLine("twodim[{0},{1}] = {2}", i2, i1, twodim[i1,i2]);
now the places of i1 and i2 are switched when they are printed.
another thing, think of twodim[i1, i2] as one value.
for the above example.
if i1 = 0 and i2 =0
twodim[i1,i2] equals 1. because that is the value of [0, 0] in the array.

Answer 2

I don't know if that explains it all.
ex:
when i1 = 0 and i2 = 0
the output will be:
twodim[0, 0] = 1

Answer 3

Your explanation is correct and easy to understand thanks