C# Program to display a string in reverse alphabetic order

To display a string in reverse order, you can convert the string to a character array and then use the Array.Reverse() method. This approach reverses the order of characters, displaying them from last to first.

Syntax

Following is the syntax for converting a string to character array −

char[] arr = str.ToCharArray();

Following is the syntax for reversing the array −

Array.Reverse(arr);

Using Array.Reverse() Method

The simplest approach is to convert the string to a character array and use Array.Reverse() to reverse the order of characters −

using System;

class Program {
   static void Main() {
      string str = "Amit";
      char[] arr = str.ToCharArray();
      Console.WriteLine("Original String: " + str);
      
      // Reverse the character array
      Array.Reverse(arr);
      Console.WriteLine("Reversed String: " + new string(arr));
   }
}

The output of the above code is −

Original String: Amit
Reversed String: timA

Using LINQ Reverse() Method

You can also use LINQ's Reverse() method with string.Concat() to achieve the same result −

using System;
using System.Linq;

class Program {
   static void Main() {
      string str = "Programming";
      Console.WriteLine("Original String: " + str);
      
      // Using LINQ Reverse
      string reversed = string.Concat(str.Reverse());
      Console.WriteLine("Reversed String: " + reversed);
   }
}

The output of the above code is −

Original String: Programming
Reversed String: gnimmargorP

Using Loop Method

You can manually reverse a string using a for loop by iterating from the last character to the first −

using System;

class Program {
   static void Main() {
      string str = "Hello";
      string reversed = "";
      Console.WriteLine("Original String: " + str);
      
      // Loop from last character to first
      for (int i = str.Length - 1; i >= 0; i--) {
         reversed += str[i];
      }
      
      Console.WriteLine("Reversed String: " + reversed);
   }
}

The output of the above code is −

Original String: Hello
Reversed String: olleH

Comparison of Methods

Conclusion

There are multiple ways to reverse a string in C#. The Array.Reverse() method is the most efficient approach, while LINQ provides the most readable solution. Choose the method that best fits your performance requirements and coding style preferences.