How to store datatable in cache to reuse it?

Question

In my application i have used Generic handler to serve requests.

I want mechanism like if the first time request comes to handler ,it makes a reques

Answer 1

Something along these lines?

public DataTable GetDataTableFromCacheOrDatabase()
{
   DataTable dataTable = HttpContext.Current.Cache["secret key"] as DataTable;
   if(dataTable == null)
   {
       dataTable = GetDataTableFromDatabase();
       HttpContext.Current.Cache["secret key"] = dataTable;
   }
   return dataTable;
}

You're going to need some mechanism to flush the data table from the cache if it changes. For example you could use an SqlCacheDependency.

As requested, to clear the cache an hour after the table is added you would do:

HttpContext.Current.Cache.Insert("secret key", dataTable, null, DateTime.Now.AddHours(1), System.Web.Caching.Cache.NoSlidingExpiration);