C# Config

Config.cs

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.IO;
using Newtonsoft.Json;

namespace Liulx.Util
{
    public class Config: INotifyPropertyChanged
    {
        private static readonly Config _default = new Config();

        public static Config Default
        {
            get { return _default; }
        }

        public string MonitorFolder
        {
            get { return GetString("MonitorFolder"); }
            set
            {
                if (GetString("MonitorFolder") != value)
                {
                    this["MonitorFolder"] = value;
                    OnPropertyChanged("MonitorFolder");
                }
            }
        }

        public string LogFolder
        {
            get { return GetString("LogFolder"); }
            set
            {
                if (GetString("LogFolder") != value)
                {
                    this["LogFolder"] = value;
                    OnPropertyChanged("LogFolder");
                }
            }
        }

        #region Config Method

        private readonly Dictionary<string, object> _configs;
        private readonly string _fileName;

        public Config(string fileName = "config.json")
        {
            _fileName = fileName;
            if (!File.Exists(_fileName))
            {
                _configs = new Dictionary<string, object>();
                File.CreateText(_fileName);
                return;
            }
            _configs = JsonConvert.DeserializeObject<Dictionary<string, object>>(File.ReadAllText(_fileName));
            _configs = _configs ?? new Dictionary<string, object>();
        }

        public object this[string index]
        {
            get { return _configs.ContainsKey(index) ? _configs[index] : null; }
            set { _configs[index] = value; }
        }

        public string GetString(string key)
        {
            try
            {
                return this[key] == null ? null : _configs[key].ToString();
            }
            catch (Exception e)
            {
                Log.CreateErrorMsg(e.Message);
            }
            return null;
        }

        public List<T> GetList<T>(string key)
        {
            try
            {
                return this[key] == null ? null : (List<T>) _configs[key];
            }
            catch (Exception e)
            {
                Log.CreateErrorMsg(e.Message);
            }
            return null;
        }

        public void Save()
        {
            string json = JsonConvert.SerializeObject(_configs, Formatting.Indented);
            File.WriteAllText(_fileName, json);
        }

        #endregion

        #region INotifyPropertyChanged
        public event PropertyChangedEventHandler PropertyChanged;

        protected void OnPropertyChanged(string propertyName)
        {
            if (PropertyChanged != null)
            {
                PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
            }
        }
        #endregion
    }
}