Can't remove white space from string in C#

Question

I am working on a file-watcher project using C# and I am trying to copy changes files into new created files, but I am getting the error: Illegal characters in the path as shown below

I think the problem comes from the white space before .4, which I have underlined in yellow. I am trying to get rid of this white space but I can't. The code is down below

    private void OnChanged(object source, FileSystemEventArgs e)
    {

        if (e.ChangeType == WatcherChangeTypes.Changed || e.ChangeType == WatcherChangeTypes.Created)
        {
            String targetname = null;
            String fn = "";
            try
            {
                bool copy = true;
                targetname = GetShortcutTarget(e.FullPath);
                if (targetname == null)
                {
                    Console.WriteLine($"File: {e.FullPath} {e.ChangeType}");
                }
                else
                {
                    c += 1;
                    fn = targetname.Replace('\\', '_').Replace(":", "_c_");
                    DateTime lmt = File.GetLastWriteTime(targetname);
                    if (lastSeen.ContainsKey(targetname))
                    {
                        if (lastSeen[targetname] < lmt)
                        {
                            copy = true;
                        }
                        else
                        {
                            copy = false;
                        }
                    }
                    else
                    {
                        lastSeen[targetname] = lmt;
                        copy = true;
                    }
                    if (copy)
                    {
                        Console.WriteLine($"Filec: {e.FullPath} {targetname} {e.ChangeType}");
                        //HERE
                        System.IO.File.Copy(targetname, $"{_lfile}\\{fn}.{c}", true);
                        // Only keep copy if copy worked
                        latest[fn] = c;
                    }
                    else
                    {
                        Console.WriteLine($"Have {e.FullPath} {targetname}");
                    }
                }
            }
            catch (Exception ex)
            {
                Console.WriteLine($"Failure to copy {e.FullPath} {targetname} {$"{_lfile}\\{fn}.{c}"} {ex.Message}");
            }
        }
        else
        {
            Console.WriteLine($"File: {e.FullPath} {e.ChangeType}");
        }
    }

I have noted a "HERE" comment to show you where the name of the file is created. I have tried many methods like Trim, Replace but it doesn't work. Can you please help me? I would be really grateful.

  namespace FileWatcher
{
    class Program
    {
        static void Main(string[] args)
        {
            String userName;
            String expt;
            if (args.Length < 2)
            {
                Console.WriteLine($"FileWatcher <user> <exptName>");
                Console.WriteLine($"Captures files into /temp/<exptName>-log and /temp/<exptName>-files");
                userName = "lashi";
                expt = "expt1";

        }
        else
        {
            userName = args[0];
            expt = args[1];
        }
        String lexpt = $"c:\\temp\\{expt}-log";
        String fexpt = $"c:\\temp\\{expt}-file";

        if (!Directory.Exists(fexpt))
        {
            Directory.CreateDirectory(fexpt);
        }
        if (!Directory.Exists(lexpt))
        {
            Directory.CreateDirectory(lexpt);
        }
        Watcher w = new Watcher(lexpt, fexpt, userName);
        w.Watch();
    }
}

class Watcher
{

    Dictionary<String, int> latest = new Dictionary<String, int>();

    String _username;
    String _ext;
    String _lfile;
    String _ffile;
    int c = 0;
    Dictionary<String, DateTime> lastSeen;


    public Watcher(String lfile, String fFile, String uName)
    {
        _username = uName;
        _ext = "*";
        _lfile = lfile;
        _ffile = fFile;
        lastSeen = new Dictionary<string, DateTime>();
        Console.CancelKeyPress += copyFiles;
    }

    public void copyFiles(object sender, ConsoleCancelEventArgs e)
    {
        Console.WriteLine("Acting on ctrl-c");
        copyFiles();
    }

    public void copyFiles()
    {
        foreach (KeyValuePair<string, int> entry in latest)
        {
            try
            {

                System.IO.File.Copy($"{_lfile}\\{entry.Key}.{entry.Value}", $"{ _ffile}\\{entry.Key}", true);
            }
            catch (Exception e)
            {
                Console.WriteLine($"Failure to take last copy {entry.Key} {entry.Value}");
            }
        }
    }

    public void Watch()
    {
        using (FileSystemWatcher watcher = new FileSystemWatcher($"C:\\Users\\{_username}\\AppData\\Roaming\\Microsoft\\Windows\\Recent", _ext))
        {
            //           watcher.Path = args[1];

            // Watch for changes in LastAccess and LastWrite times, and
            // the renaming of files or directories.
            watcher.NotifyFilter = NotifyFilters.LastAccess
                                 | NotifyFilters.LastWrite
                                 | NotifyFilters.FileName
                                 | NotifyFilters.DirectoryName;

            // Only watch text files.
            // watcher.Filter = "*.txt";
            watcher.IncludeSubdirectories = false;
            // Add event handlers.
            watcher.Changed += OnChanged;
            watcher.Created += OnChanged;
            watcher.Deleted += OnChanged;
            watcher.Renamed += OnRenamed;


            // Begin watching.
            watcher.EnableRaisingEvents = true;

            // Wait for the user to quit the program.
            Console.WriteLine("Press 'q' to quit the sample.");
            while (Console.Read() != 'q') ;
        }
        // After a q then 
    }

Failure to copy C:\Users\lashi\AppData\Roaming\Microsoft\Windows\Recent\MSIX+VHD.docx.lnk C:\Users\lashi\Desktop\Klera_Internship\MSIX+VHD.docx  c:\temp\expt1-log\C_c__Users_lashi_Desktop_Klera_Internship_MSIX+VHD.docx .1 Illegal characters in path.

Answer 1

I don't see you actually trying to strip whitespace, nor do I see where you're getting rid of those brackets. I also didn't like typing out your paths -- I hope I didn't get them wrong. Maybe you can see now why everyone was asking you to provide actual text for your values, not screenshots...

Personally, I would make use of regex and limit characters to alphanumeric and maybe a couple of other special characters (like underscore). You can modify the regex as needed and add additional special characters. There is a risk, however, that you will get 2 files that don't have the same original names, but do have the same target names (eg 'test one.jpg' and 'testone.jpg), so you should think about that.

Perhaps an approach like this may be better:

using System;
using System.Text.RegularExpressions;
                    
public class Program
{
    public static void Main()
    {
        var fn = "";
        var targetname = @"C:\Users\lashi\Desktop\Klera_Internship (2).lnk";
        var _lfile = @"c:\temp\expt1-log";
        var c = 12; // arbitrary int

        // what you're doing now... I don't see you trying to clean any spaces, nor brackets:
        fn = targetname.Replace('\\', '_').Replace(":", "_c_");

        Console.WriteLine($"Target Before: {targetname}");
        Console.WriteLine($"Destination Before: {_lfile}\\{fn}.{c}");
        
        // what you could do with a few more replacements:
        fn = targetname.ToSafeFilename();
        
        Console.WriteLine($"Target After: {targetname}");
        Console.WriteLine($"Destination After: {_lfile}\\{fn}.{c}");
        
    }
}
public static class StringExtensions{
    public static string ToSafeFilename(this string inString)
    {
        inString = Regex.Replace(inString, @"\\", "_");
        inString = Regex.Replace(inString, @":", "_c_");
        return Regex.Replace(inString, @"[^0-9a-zA-Z_]+", "");
    }
}

Output:

//Target Before: C:\Users\lashi\Desktop\Klera_Internship (2).lnk
//Destination Before: c:\temp\expt1-log\C_c__Users_lashi_Desktop_Klera_Internship (2).lnk.12
//Target After: C:\Users\lashi\Desktop\Klera_Internship (2).lnk
//Destination After: c:\temp\expt1-log\C_c__Users_lashi_Desktop_Klera_Internship2lnk.12

See:

https://dotnetfiddle.net/MfTyYo