ASP。NET缓存总是返回null-ASP.NETCachealwaysreturnsnull

I am using SQLCacheDependency in my ASP.NET application with Query Notifications. I followed this article to set up my database with success.However whenever I am trying to store data in the cache object.It just does not hold value.It is always null .I am not getting any errors or exceptions. Here is my code

我在我的ASP中使用SQLCacheDependency。带有查询通知的NET应用程序。我根据本文成功地建立了我的数据库。但是，每当我试图在缓存对象中存储数据时。它只是没有价值。它总是null，我没有任何错误或异常。这是我的代码

Global.asax

Global.asax

void Application_Start(object sender, EventArgs e)
    {
        // Code that runs on application startup
        System.Data.SqlClient.SqlDependency.
        Start(ConfigurationManager.ConnectionStrings["McdConn"].ToString());

    }

void Application_End(object sender, EventArgs e)
    {
        //  Code that runs on application shutdown
        System.Data.SqlClient.SqlDependency.
        Stop(ConfigurationManager.ConnectionStrings["McdConn"].ToString());
    }

public static class CacheManagement
{
    public static DataTable CreateCache(string cacheName, string tableName, string query)
    {
        DataTable dtResult = new DataTable();
        try
        {
            string cOnnectionString= ConfigurationManager.ConnectionStrings["McdConn"].ToString();
            dtResult = HttpContext.Current.Cache[cacheName] as DataTable;

            if (dtResult == null)
            {
                dtResult = new DataTable();
                using (var cn = new SqlConnection(connectionString))
                {
                    cn.Open();
                    var cmd = new SqlCommand(query, cn);
                    cmd.Notification = null;
                    cmd.NotificatiOnAutoEnlist= true;
                    SqlCacheDependencyAdmin.EnableNotifications(connectionString);
                    if (!SqlCacheDependencyAdmin.GetTablesEnabledForNotifications(connectionString).Contains(tableName))
                    {
                        SqlCacheDependencyAdmin.EnableTableForNotifications(connectionString,tableName);
                    }

                    var dependency = new SqlCacheDependency(cmd);
                    //SqlDataAdapter ad = new SqlDataAdapter(cmd);
                    //ad.Fill(dsResult);
                    SqlDataReader reader = cmd.ExecuteReader();
                    dtResult.Load(reader);
                    HttpContext.Current.Cache.Insert(cacheName, dtResult, dependency);

                }
            }
        }
        catch (Exception ex)
        {
            Exception_Log.ExceptionMethod("Web", "CacheManagement.cs", "CacheManagement", ex);
        }

        return dtResult = HttpContext.Current.Cache[cacheName] as DataTable;
    }

}

Code Behind

后面的代码

var dtCachedCategories = HttpContext.Current.Cache["tbl_CategoryMaster_Cached"] as DataTable;
if (dtCachedCategories == null)
{
 dtCachedCategories = CacheManagement.CreateCache("tbl_CategoryMaster_Cached","dbo.tbl_CategoryMaster_Languages", "Select * from dbo.tbl_CategoryMaster_Languages");

}

The above always returns null.

上面的总是返回null。

Can anyone help me in pointing out what could be missing?

谁能帮我指出可能遗漏了什么吗?

1 个解决方案

System.Web.HttpRuntime.Cache.Insert(cacheName, dtResult, dependency);