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C# Pointer in unsafe context

Pointer usage in C# in unsafe context

static unsafe void Main()
{
    int i;
    int[] array = { 11, 22, 33 };

    // pointer pi has the address of variable i
    int* pi = &i;

    i = 0;
    // dereference the pi, i.e. *pi is i
    Console.WriteLine("i = {0}", *pi); // output: i = 0
    // since *pi is i, equivalent to i++
    (*pi)++;
    Console.WriteLine("i = {0}", *pi); // output: i = 1

    // pointer ppi has the address 
    // of variable pi
    int** ppi = π
    // since *ppi is pi, one more dereference  *pi is i
    // equivalent to i += 2
    **ppi += 2;
    Console.WriteLine("i = {0}", *pi);// output: i = 3

    // pointer to an array
    fixed (int* parray = array)
    {
        // get a copy of parray in fixed context.
        int* p = parray;
        Console.WriteLine(*(p++));// output: 11
        Console.WriteLine(*(p++));// output: 22
        Console.WriteLine(*(p++));// output: 33
    }
    Console.ReadLine();
}