如何从 c# 数组中的第 2 项切片元素？

Question

Given a 1D array,

double[] arr = { 4, 3, 2, 8, 7, 6, 1 };

I want to get values from 2nd index till last and want to store the array in a variable. Want to get something like this:

new_arr = {3, 2, 8, 7, 6, 1 }; //first element sliced

Answer 1

You can use C# 8 indices and ranges feature

double[] arr = { 4, 3, 2, 8, 7, 6, 1 };
var slice = arr[1..];

It'll return all items from index 1 till the end of array and give you an expected slice {3, 2, 8, 7, 6, 1 } . Again, it works only with C# 8 and .NET Core 3.x.

For earliest versions of C# you should do this by yourself, using Array.Copy for example or System.Linq

double[] arr = { 4, 3, 2, 8, 7, 6, 1 };
var slice = arr.Skip(1).ToArray();

Answer 2

If you are using C# 8, you can use Indices & Range . It goes something like this:

var newArray = oldArray[1..];  // Takes everything from index 1 until the end.

Answer 3

You can use Linq to skip the fist item and take the rest. This will give you the sequence:

arr.Skip(1);

Which you can convert to a new array like this:

var new_arr = arr.Skip(1).ToArray();