c# - MVC Net Core 将 MemoryCache 传递给所有控制器

Question

我正在建立一个在线商店网站。我想将 ProductCategory 显示为侧边栏（短列表类别，例如衣服、电子产品、家具、书籍等）。

最后，我想将 productcategory _cache 变量发送给所有控制器。这种方法看起来正确吗？另外，如何删除 Home Controller 中不必要的 memorycache 参数？在 Scheduled stuff 中创建一个方法来检索它？

DI解决方案：

public class HomeController : Controller
{    
   private readonly IMemoryCache _cache;
   public IScheduledStuff _scheduledstuff;
   public HomeController(IMemoryCache cache, IScheduledStuff scheduledstuff)
   {
        _cache = cache;
        _scheduledstuff = scheduledstuff;
        _scheduledstuff.ScheduleItemsExecute();
    }
    public IActionResult Index()
    {
        ViewBag.ProductCategoryList = _cache.Get<IEnumerable<ProductCategory>>("Teststore");
        return View();
    }
}

public class ProductCategoryRepository : IProductCategoryRepository<ProductCategory>
{
    public IEnumerable<ProductCategory> GetAllProductCategory()
    {
        return _context.ProductCategory.ToList();
    }
}

public ProductCategory()
{
    public int ProductCategoryId { get; set; }
    public string ProductCategoryName { get; set; }
    public string ProductCategoryDescription { get; set; }
}

public class ScheduledStuff : IScheduledStuff
{
    private readonly DatabaseContext _context;
    IMemoryCache MemCache;
    public IProductCategoryRepository<ProductCategory> productcategoryrepository;

    public ScheduledStuff(DatabaseContext context, IMemoryCache memCache)
    {
        _context = context;
        MemCache = memCache;
        productcategoryrepository = new ProductCategoryRepository(_context);
    }

    public void ScheduleItemsExecute()
    {
        var testdata = productcategoryrepository.GetAllProductCategory();
        MemCache.Set("Teststore", testdata);
    }
}


public class Startup
{
    public IProductCategoryRepository<ProductCategory> productcategoryrepository;
    public IMemoryCache memorycache;

    public void ConfigureServices(IServiceCollection services)
    {
        services.AddMemoryCache();
        services.AddSingleton<ScheduledStuff>();

Asp.Net Core：在控制器外使用内存缓存

解决方案静态：不断收到 Null 异常错误，有人可以帮助解决这个问题吗？

public static class MemoryCacheStatic
{
    public static IMemoryCache MemCacheStatic;
    public static IProductCategoryRepository<ProductCategory> productcategoryrepositorystatic;

    // Error on this line: <--- NullReferenceException: Object reference not set to an instance of an object.
    public static IEnumerable<ProductCategory> ProductCategoryStatic = productcategoryrepositorystatic.GetAllProductCategory();   


     public static void SetValues()
     {
        ProductCategoryStatic = productcategoryrepositorystatic.GetAllProductCategory();
        MemCacheStatic.Set("Teststore", ProductCategoryStatic) ;
     }

标签： c#memoryasp.net-corememorycache

Answer 1

这应该可以，谢谢你的帮助 Henk-

public class HomeController : Controller
{    
   private readonly IMemoryCache _cache;
   public IScheduledStuff _scheduledstuff;
   public HomeController(IMemoryCache cache, IScheduledStuff scheduledstuff)
   {
        _cache = cache;
        _scheduledstuff = scheduledstuff;
        _scheduledstuff.ScheduleItemsExecute();
    }
    public IActionResult Index()
    {
        ViewBag.ProductCategoryList = _cache.Get<IEnumerable<ProductCategory>>("Teststore");
        return View();
    }
}

public class ProductCategoryRepository : IProductCategoryRepository<ProductCategory>
{
    public IEnumerable<ProductCategory> GetAllProductCategory()
    {
        return _context.ProductCategory.ToList();
    }
}

public ProductCategory()
{
    public int ProductCategoryId { get; set; }
    public string ProductCategoryName { get; set; }
    public string ProductCategoryDescription { get; set; }
}

public class ScheduledStuff : IScheduledStuff
{
    private readonly DatabaseContext _context;
    IMemoryCache MemCache;
    public IProductCategoryRepository<ProductCategory> productcategoryrepository;

    public ScheduledStuff(DatabaseContext context, IMemoryCache memCache)
    {
        _context = context;
        MemCache = memCache;
        productcategoryrepository = new ProductCategoryRepository(_context);
    }

    public void ScheduleItemsExecute()
    {
        var testdata = productcategoryrepository.GetAllProductCategory();
        MemCache.Set("Teststore", testdata);
    }
}


public class Startup
{
    public IProductCategoryRepository<ProductCategory> productcategoryrepository;
    public IMemoryCache memorycache;

    public void ConfigureServices(IServiceCollection services)
    {
        services.AddMemoryCache();
        services.AddSingleton<ScheduledStuff>();