int[] myarray = new int[]{1,2,3,4};
for(int i = myarray.Length - 1; i >= 0; i--)
{
Console.WriteLine(i);
}
for (int i = myArray.Length; i --> 0; )
{
//do something
}
string[] arr = new string[5];
for (int a = arr.Length; --a >= 0;)
{
// ...
}