Example. Here we see a generic method, which lets it act on any type. Our Slice method here uses this ability to simulate the built-in slice functionality of Python and other languages.
Extensions This class contains a public static method called Slice. The Slice method is an extension method.
Extension
Also The other confusing part is the use of the letter T. The Type T is replaced by the C# compiler with any type you specify.
C# program that slices array
using System;
using System.Collections.Generic;
class Program
{
static void Main()
{
int[] a = new int[]
{
1,
2,
3,
4,
5,
6,
7
};
foreach (int i in a.Slice(0, 1))
{
Console.WriteLine(i);
}
Console.WriteLine();
foreach (int i in a.Slice(0, 2))
{
Console.WriteLine(i);
}
Console.WriteLine();
foreach (int i in a.Slice(2, 5))
{
Console.WriteLine(i);
}
Console.WriteLine();
foreach (int i in a.Slice(2, -3))
{
Console.WriteLine(i);
}
}
}
public static class Extensions
{
/// <summary>
/// Get the array slice between the two indexes.
/// ... Inclusive for start index, exclusive for end index.
/// </summary>
public static T[]
Slice<T>(this T[] source, int start, int end)
{
// Handles negative ends.
if (end < 0)
{
end = source.Length + end;
}
int len = end - start;
// Return new array.
T[] res = new T[len];
for (int i = 0; i < len; i++)
{
res[i] = source[i + start];
}
return res;
}
}
1
1
2
3
4
5
3
4
A discussion. How is this method different from LINQ Take and Skip? The method here can deal with negative parameters. And it may be faster because it doesn't use IEnumerable.
Take, TakeWhile
Skip, SkipWhile
Note James Kolpack wrote in with a correction of the end computation and I added a test for that case.
Strings In my development efforts, I have also used string slice methods, which are proven equivalent in the main aspects to JavaScript.
String Slice
