mapo-core/MP.Data/Services/LocalStorageService.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Text.Json;
using Microsoft.JSInterop;

namespace MP.Data.Services
{
    public interface ILocalStorageService
    {
        #region Public Methods

        Task ClearAsync();
        Task<bool> ContainKeyAsync(string key);
        Task<T?> GetItemAsync<T>(string key);
        Task<T> GetItemAsync<T>(string key, T fallback);
        Task RemoveItemAsync(string key);
        Task SetItemAsync<T>(string key, T value);

        #endregion Public Methods
    }

    public class LocalStorageService : ILocalStorageService
    {
        #region Public Constructors

        public LocalStorageService(IJSRuntime js)
        {
            _js = js;
        }

        #endregion Public Constructors

        #region Public Methods

        public async Task ClearAsync()
        {
            await _js.InvokeVoidAsync("localStorage.clear");
        }

        public async Task<bool> ContainKeyAsync(string key)
        {
            var value = await _js.InvokeAsync<string>("localStorage.getItem", key);
            return value != null;
        }

        public async Task<T?> GetItemAsync<T>(string key)
        {
            var json = await _js.InvokeAsync<string>("localStorage.getItem", key);

            if (json is null)
                return default;

            return JsonSerializer.Deserialize<T>(json);
        }

        public async Task<T> GetItemAsync<T>(string key, T fallback)
        {
            var json = await _js.InvokeAsync<string>("localStorage.getItem", key);

            if (json is null)
                return fallback;

            return JsonSerializer.Deserialize<T>(json) ?? fallback;
        }

        public async Task RemoveItemAsync(string key)
        {
            await _js.InvokeVoidAsync("localStorage.removeItem", key);
        }

        public async Task SetItemAsync<T>(string key, T value)
        {
            var json = JsonSerializer.Serialize(value);
            await _js.InvokeVoidAsync("localStorage.setItem", key, json);
        }

        #endregion Public Methods

        #region Private Fields

        private readonly IJSRuntime _js;

        #endregion Private Fields
    }
}