How to Create a Range From a Specified Start in C#?

The Range Structure is introduced in C# 8.0. It represents a range that has a start and end indexes. You are allowed to create a Range object starting from the specified starting index to the end of the given collection or sequence with the help of the StartAt() Method provided by the Range structure. Or in other words, StartAt() Method returns a range that starts from the specified start index to the end of the given collection or sequence.

Syntax:

public static Range StartAt(Index start);

Here, the Index start represents the start index.

Example 1:

// C# program to illustrate
// how to create a range using
// StartAt() method of Range struct
using System;

namespace range_example {

class GFG {

    // Main Method
    static void Main(string[] args)
    {
        // Creating range
        // using Range constructor
        var r1 = new Range(2, 4);

        // Creating range
        // using Range operator
        Range r2 = 1..10;

        // Creating a range
        // using StartAt() method
        var r3 = Range.StartAt(4);

        // Displaying all the ranges
        Console.WriteLine("Range_1: " + r1);
        Console.WriteLine("Range_2: " + r2);
        Console.WriteLine("Range_3: " + r3);
    }
}
}

Output:

Range_1: 2..4
Range_2: 1..10
Range_3: 4..^0

Example 2:

// C# program to illustrate how
// to create a range using
// StartAt() method of Range struct
using System;

namespace range_example {

class GFG {

    // Main Method
    static void Main(string[] args)
    {
        // Creating and initializing an array
        int[] arr = new int[8] {100, 200, 300,
                     400, 500, 600, 700, 800};

        // Creating a range
        // using StartAt() method
        var r = Range.StartAt(2);
        var new_arr = arr[r];

        // Displaying the range
        // and the elements
        Console.WriteLine("Range: " + r);
        Console.Write("Numbers: ");

        foreach(var i in new_arr)
            Console.Write($" [{i}]");
    }
}
}

Output:

Range: 2..^0
Numbers:  [300] [400] [500] [600] [700] [800]