Creating an Index From the Specified Index at the Start of a Collection in C#

The Index Structure is introduced in C# 8.0. It represents a type that can be used to index a collection or sequence and it can be started from the start or the end. You are allowed to create a start index with the help of the FromStart(Int32) Method() provided by the Index struct. This method returns an index from the start of the given collection or sequence at a specified position.

Syntax:

public static Index FromStart(int value);

Example 1:

// C# program to illustrate the
// concept of the FromStart() method
using System;

namespace example {

class GFG {

    // Main Method
    static void Main(string[] args)
    {
        // Creating start index
        // Using FromStart() method
        var in1 = Index.FromStart(2);
        var in2 = Index.FromStart(1);
        var in3 = Index.FromStart(0);
        var in4 = Index.FromStart(6);

        // Displaying  index value
        Console.WriteLine("Index position is : {0} ", in1);
        Console.WriteLine("Index position is : {0} ", in2);
        Console.WriteLine("Index position is : {0} ", in3);
        Console.WriteLine("Index position is : {0} ", in4);
    }
}
}

Output:

Index position is : 2 
Index position is : 1 
Index position is : 0 
Index position is : 6 

Example 2:

// C# program to illustrate the
// concept of the FromStart() method
using System;

namespace example {

class GFG {

    // Main Method
    static void Main(string[] args)
    {
        // Creating and initializing an array
        string[] greetings = new string[] {"Hello", "Hola", "Namaste",
                                "Bonjour", "Ohayo", "Ahnyounghaseyo"};

        // Creating start index
        // Using FromStart() method
        var index_1 = Index.FromStart(0);
        var index_2 = Index.FromStart(1);
        var index_3 = Index.FromStart(4);
        var index_4 = Index.FromStart(5);

        // Displaying index and their values
        Console.WriteLine("Index: {0} Value: {1}",
                    index_1, greetings[index_1]);

        Console.WriteLine("Index: {0} Value: {1}",
                    index_2, greetings[index_2]);

        Console.WriteLine("Index: {0} Value: {1}",
                    index_3, greetings[index_3]);

        Console.WriteLine("Index: {0} Value: {1}",
                    index_4, greetings[index_4]);
    }
}
}

Output:

Index: 0 Value: Hello
Index: 1 Value: Hola
Index: 4 Value: Ohayo
Index: 5 Value: Ahnyounghaseyo