File Renaming App v1.0

using System;
using System.Linq;
using System.IO;

namespace FebTwoTwo
{
    class Program
    {
        static void Main(string[] args)
        {
            //Ask user for path. Verify that path exists.
            bool invalidPath;
            string rootPath;
            do
            {
                Console.Write("Please enter the location of the files you would like to rename: ");
                rootPath = Console.ReadLine();
                invalidPath = false;

                if ( !(Directory.Exists(rootPath)) )
                {
                    invalidPath = true;
                    Console.Clear();
                    Console.WriteLine("You entered {0}. This file path does not exist.", rootPath);
                }
            }
            while (invalidPath);

            //define DirectoryInfo and FileInfo
            DirectoryInfo info = new DirectoryInfo(rootPath);
            FileInfo[] files = info.GetFiles().OrderBy(p => p.CreationTime).ToArray();

            //inform user of which files are at the specified location
            Console.WriteLine("You entered \"{0}\". Flies at current location:", rootPath);
            foreach (FileInfo file in files)
            {
                Console.WriteLine(file);
            }

            //Get file name to batch rename, make sure file name is valid.
            bool fileNameError;
            string batchFileName;
            do
            {
                Console.WriteLine("Please enter name you would like to rename files to:");
                batchFileName = Console.ReadLine();
                fileNameError = false;
                if (ContainsInvalidChars(batchFileName))  // invalid chars are \/:*?"<>|
                {
                    fileNameError = true;
                    Console.Clear();
                    Console.WriteLine("The file name {0} contains an invalid character. \nPlease use another name.", batchFileName);
                }
            }
            while (fileNameError);

            //verify user would like to continue, get input whether or not to continue.
            Console.WriteLine("You entered \"{0}\". Would you like to continue? (Type 'Y' or 'N')", batchFileName);
            string proceedInput = Console.ReadLine();
            bool charParseSuccess = char.TryParse(proceedInput, out char proceedAsChar);

            //if user types 'Y' then rename files, else exit program
            if ( (charParseSuccess && proceedAsChar == 'Y') || (charParseSuccess && proceedAsChar == 'y'))
            {
                //Change file names
                int counter = 1;
                foreach (FileInfo file in files)
                {
                    string name = file.Name;            //file name with extension, without path
                    string extension = file.Extension;  //extension
                    string fullName = file.FullName;    //full file path including extension
                                                        //Console.WriteLine(file.Name);

                    File.Move(file.FullName, file.FullName.Replace(file.Name, batchFileName + counter.ToString() + file.Extension));

                    //Console.WriteLine(oldDate.ToString());
                    counter++;

                    //File.Move takes the path of the original file (file.FullName) and moves it to the destination path (File.FullName.Replace)
                    //Replace takes the old string (original path) and replaces it with a new path
                    //Example it changes C:\temp\picture.jpeg to C:\temp\MyFile1.jpeg
                }
                Console.WriteLine("{0} Files Renamed", counter - 1);
            }
             else
            {
                Console.WriteLine("Rename Cancelled. Press any key to exit");
            }
            Console.Read();
        }
        public static bool ContainsInvalidChars(string userInput) // Method to check if file contains any invalid chars
        {
            if ((userInput.Contains('/')) ||
                 (userInput.Contains('\\')) ||
                 (userInput.Contains(':')) ||
                 (userInput.Contains('*')) ||
                 (userInput.Contains('?')) ||
                 (userInput.Contains('"')) ||
                 (userInput.Contains('<')) ||
                 (userInput.Contains('>')) ||
                 (userInput.Contains('|'))
                 )
            {
                return true;
            }
            else
            {
                return false;
            }
        }
    }
}