WCS/Cowain.Base/Helpers/GlobalData.cs

using Cowain.Base.Models;
using Cowain.Base.ViewModels;
using System.ComponentModel;
using System.Reflection;
using System.Runtime.CompilerServices;

namespace Cowain.Base.Helpers;

public class GlobalData : INotifyPropertyChanged
{
    public event PropertyChangedEventHandler? PropertyChanged;
    public void RaisePropertyChanged([CallerMemberName] string? propertyName = null)
    {
        PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
    }
    private static GlobalData? _instance;
    private static readonly object _lock = new object();
    private GlobalData()
    {
    }

    public static GlobalData Instance
    {
        get
        {
            if (_instance == null)
            {
                lock (_lock)
                {
                    if (_instance == null)
                    {
                        _instance = new GlobalData();
                    }
                }
            }
            return _instance;
        }
    }

    private IDictionary<string, object> _activeDictionary = new Dictionary<string, object>();

    public LoginUserViewModel? CurrentUser { get; set; }
    public void AddOrUpdate(string key, object? value)
    {
        if (value is null)
        {
            return;
        }
        if (_activeDictionary.ContainsKey(key))
        {
            _activeDictionary[key] = value;
            //字典中的值发生变化时，触发PropertyChanged事件
            RaisePropertyChanged("Item");
        }
        else
        {
            _activeDictionary.Add(key, value);
            // 添加新键时通知整个索引器
            RaisePropertyChanged("Item[]");
        }
    }


    public object? this[string key]
    {
        get
        {
            return _activeDictionary.TryGetValue(key, out var value) ? value : null;
        }

    }
}