How do I clone a range of array elements to a new array?

Question

I have an array X of 10 elements. I would like to create a new array containing all the elements from X that begin at index 3 and ends in index 7. Sure I can easily write a

Answer 1

In C# 8, they've introduced a new Range and Index type, which can be used like this:

int[] a = { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 };
Index i1 = 3;  // number 3 from beginning
Index i2 = ^4; // number 4 from end
var slice = a[i1..i2]; // { 3, 4, 5 }

References:

• https://docs.microsoft.com/en-us/dotnet/core/whats-new/dotnet-core-3-0#ranges-and-indices
• https://devblogs.microsoft.com/dotnet/building-c-8-0/