What is the method for initializing a two-dimensional array in C#?

In C#, there are several methods available to initialize a two-dimensional array.

1. Initialize array elements one by one using a loop.

int[,] array = new int[3, 4];
for (int i = 0; i < array.GetLength(0); i++)
{
    for (int j = 0; j < array.GetLength(1); j++)
    {
        array[i, j] = i + j;
    }
}

1. Initialize array elements using array initializer.

int[,] array = new int[,]
{
    {1, 2, 3},
    {4, 5, 6},
    {7, 8, 9}
};

1. Initialize array elements using simplified array initializer.

int[,] array = {
    {1, 2, 3},
    {4, 5, 6},
    {7, 8, 9}
};

The first method is suitable for cases where array elements need to be initialized based on a specific logic, while the last two methods are suitable for cases where the specific values of array elements are already known.