Enterprise Code #7 : Watching a File or Directory using FileSystemWatcher

CustomWatcher.cs

public class CustomWatcher
{
    private FileSystemWatcher _watcher;

    private bool IsWatching;
    private StringBuilder strMsg = new StringBuilder();

    private bool IncludeSubFolder = false; // SubFolder Check 
    private bool DirectoryCheck; // Directory // Folder
    // !DirectoryCheck           // File        
    private string path;

    //Singleton pattern   
    private static CustomWatcher _current = null;
    private static object _lockObj = new object();

    public static CustomWatcher Current(string path,bool isDirectory,bool includeSubFolder)
    {
        if (_current == null)
        {
            lock (_lockObj)
            {
                if (_current == null)
                {
                    _current = new CustomWatcher(path,isDirectory,includeSubFolder);
                }
            }
        }

        return _current;
    }
        
    private CustomWatcher(string path,bool isDirectory,bool includeSubFolder)
    {
        this.IsWatching = false;

        this.path = path;
        this.DirectoryCheck = isDirectory;
        this.IncludeSubFolder = includeSubFolder;
    }

    public void Watch() 
    {
        if (IsWatching) 
        {
            IsWatching = false;
            _watcher.EnableRaisingEvents = false;
            _watcher.Dispose();
            //strMsg.Append("Stop Watching....\n");
        }
        else
        {
            IsWatching = true;
            //strMsg.Append("Start Watching ...\n");

            _watcher = new FileSystemWatcher();
            if (DirectoryCheck)
            {
                //Directory
                _watcher.Filter = "*.*";
                _watcher.Path = path + "\\";

                if (IncludeSubFolder)
                {
                    _watcher.IncludeSubdirectories = true;
                }
            }
            else
            {
                //File
                _watcher.Filter = path.Substring(path.LastIndexOf('\\') + 1);
                _watcher.Path = path.Substring(0, path.Length - _watcher.Filter.Length);
            }

            _watcher.NotifyFilter = NotifyFilters.LastAccess | 
                                    NotifyFilters.LastWrite  | 
                                    NotifyFilters.FileName | 
                                    NotifyFilters.DirectoryName;

            _watcher.Changed += _watcher_Changed;
            _watcher.Created += _watcher_Created;
            _watcher.Deleted += _watcher_Deleted;
            _watcher.Renamed += _watcher_Renamed;
            //_watcher.Error += _watcher_Error;

            _watcher.EnableRaisingEvents = true;
        }
    }

    void _watcher_Renamed(object sender, RenamedEventArgs e)
    {
        strMsg.Remove(0, strMsg.Length);
        strMsg.Append(e.OldFullPath);
        strMsg.Append(" ");
        strMsg.Append(e.ChangeType.ToString());
        strMsg.Append(" ");
        strMsg.Append("to ");
        strMsg.Append(e.Name);
        strMsg.Append("    ");
        strMsg.Append(DateTime.Now.ToString());

        //File
        if (!this.DirectoryCheck)
        {
            _watcher.Filter = e.Name;
            _watcher.Path = e.FullPath.Substring(0, e.FullPath.Length - _watcher.Filter.Length);
        }
            
        Console.WriteLine(strMsg.ToString());           
    }

    void _watcher_Error(object sender, ErrorEventArgs e)
    {
        throw new NotImplementedException();
    }

    void _watcher_Deleted(object sender, FileSystemEventArgs e)
    {
        strMsg.Remove(0, strMsg.Length);
        strMsg.Append(e.FullPath);
        strMsg.Append(" ");
        strMsg.Append(e.ChangeType.ToString());
        strMsg.Append("    ");
        strMsg.Append(DateTime.Now.ToString());
         
        Console.WriteLine(strMsg.ToString());
    }

    void _watcher_Created(object sender, FileSystemEventArgs e)
    {
           
        strMsg.Remove(0, strMsg.Length);
        strMsg.Append(e.FullPath);
        strMsg.Append(" ");
        strMsg.Append(e.ChangeType.ToString());
        strMsg.Append("    ");
        strMsg.Append(DateTime.Now.ToString());

        Console.WriteLine(strMsg.ToString());
    }

    void _watcher_Changed(object sender, FileSystemEventArgs e)
    {            
        strMsg.Remove(0, strMsg.Length);
        strMsg.Append(e.FullPath);
        strMsg.Append(" ");
        strMsg.Append(e.ChangeType.ToString());
        strMsg.Append("    ");
        strMsg.Append(DateTime.Now.ToString());

        Console.WriteLine(strMsg.ToString());
    }

}