Few lines code for boost the performance by in-memory cache

CacheHelper.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Runtime.Caching;

namespace Dev.Lib
{
    public class CacheHelper
    {
        public static T GetOrSet<T>(string cacheKey, DateTime expiredAt, Func<T> getItemCallback) where T : class
        {
            T item = MemoryCache.Default.Get(cacheKey) as T;
            if (item == null)
            {
                item = getItemCallback();
                MemoryCache.Default.Add(cacheKey, item, expiredAt);
            }
            return item;
        }
    }
}