c# interview questions and answers - Part 6 Real time example of recursion

Part 6 Real time example of recursion

Link for code samples used in the demo
http://csharp-video-tutorials.blogspot.com/2013/10/part-6-real-time-example-of-recursion.html

Link for csharp, asp.net, ado.net, dotnet basics, mvc and sql server video tutorial playlists
http://www.youtube.com/user/kudvenkat/playlists

This is continuation to Part 5. Please watch Part 5 from C# Interview Questions tutorial before proceeding.

Probably in an interview, an interviewer may ask you to give an example, where you have used recursion in your project.
To find all the files in a folder and in all the sub-folders in the hierarchy. This is a very good example of where we could use recursion.

// find all files in subdirectories c#.png

Please make sure to include the following using declaration.
using System.IO;

public class Program
{
public static void Main()
{
// Prompt the user to enter folder path
Console.WriteLine(“Please enter folder path”);
// Read the path from the console
string folderPath = Console.ReadLine();

// Invoke FindFiles() recursive function
FindFiles(folderPath);
}

private static void FindFiles(string path)
{
// Loop thru each file in the current directory and print it’s name
foreach (string fileName in Directory.GetFiles(path))
{
Console.WriteLine(fileName);
}

// If there is a subdirectory in the current directory, then recursively call FindFiles() method.
// The recursion will break when the innermost directory with no subdirectory is found.
foreach (string directory in Directory.GetDirectories(path))
{
// Notice that FindFiles() is calling itself
FindFiles(directory);
}
}
}