C# console process indicator

ProcessIndicator.cs

    class ProcessIndicator : IDisposable  {
        public ProcessIndicator(string message, int count, int step = 1, Func<string, int, int, int, string> getIndicator = null) {
            _count = count;
            _step = step;
            _counter = 0;
            _getIndicator = getIndicator ?? Bar;

            Console.Write(message + " ");
        }

        public void Tick(string tickMessage = "", params object[] args) {
            _counter++;
            var message = string.Format(tickMessage, args);
            var processIndicator = _getIndicator(message, _counter, _count, _step);

            Erase(processIndicator.Length);
            Console.Write(processIndicator);
        }

        public void Dispose() {
            var done = ("[Done]" + new string(' ', _eraser.Length));
            Erase(0);
            Console.WriteLine(done);
        }

        private void Erase(int length) {
            Console.Write(_eraser);
            if(length != _eraser.Length)
                _eraser = new string('\b', length);
        }

        public static string Bar(string message, int current, int total, int step) {
            var length = (double)total/step;
            var curr = (int) Math.Floor(current/length);
            return string.Format("{1}[{0,-" + step + "}]", new string('I', curr), message);
        }

        public static string Spinner(string message, int current, int total, int step) {
            var mod = current%4; 
            var spinner = "";
            switch (mod) {
                case 0: spinner = "/"; break; case 1: spinner = "-"; break;
                case 2: spinner = "\\";break; case 3: spinner = "|";break;
            }
            return spinner; 
        }


        public static string Percentage(string message, int current, int total, int step) {
            var perc = Math.Ceiling(100d*current/total);
            return string.Format("{1}[{0,3}%]", perc, message);
        }

        private readonly Func<string, int, int, int, string> _getIndicator; 

        private string _eraser = "";
        private int _counter;
        private readonly int _count;
        private readonly int _step;
    }