How to pass down the System.Web.Cache to my service layer

Question

I am using unity for IOC.

In my service layer I want to use the System.Web.Cache in my class.

Should I just pass that as a parameter and Unity will automatically pass that as dependancy?

example:

public class UserService
{
   public UserService(System.Web.Caching.Cache cache)
   {
     _cache = cache;
   }
}

Answer 1

You should use System.Runtime.Caching. It is specially designed to handle caching of Object. NopCommerce has great implementation for this. You should created a CacheManager like:

/// <summary>
    /// Cache manager interface
    /// </summary>
    public interface ICacheManager
    {
        /// <summary>
        /// Gets or sets the value associated with the specified key.
        /// </summary>
        /// <typeparam name="T">Type</typeparam>
        /// <param name="key">The key of the value to get.</param>
        /// <returns>The value associated with the specified key.</returns>
        T Get<T>(string key);

        /// <summary>
        /// Adds the specified key and object to the cache.
        /// </summary>
        /// <param name="key">key</param>
        /// <param name="data">Data</param>
        /// <param name="cacheTime">Cache time</param>
        void Set(string key, object data, int cacheTime);

        /// <summary>
        /// Gets a value indicating whether the value associated with the specified key is cached
        /// </summary>
        /// <param name="key">key</param>
        /// <returns>Result</returns>
        bool IsSet(string key);

        /// <summary>
        /// Removes the value with the specified key from the cache
        /// </summary>
        /// <param name="key">/key</param>
        void Remove(string key);

        /// <summary>
        /// Removes items by pattern
        /// </summary>
        /// <param name="pattern">pattern</param>
        void RemoveByPattern(string pattern);

        /// <summary>
        /// Clear all cache data
        /// </summary>
        void Clear();
    }

And then you can implement the ICacheManager interface with MemoryCache or any other cache manager like RedisCache as below:

 /// <summary>
    /// Represents a MemoryCacheCache
    /// </summary>
    public partial class MemoryCacheManager : ICacheManager
    {
        protected ObjectCache Cache
        {
            get
            {
                return MemoryCache.Default;
            }
        }

        /// <summary>
        /// Gets or sets the value associated with the specified key.
        /// </summary>
        /// <typeparam name="T">Type</typeparam>
        /// <param name="key">The key of the value to get.</param>
        /// <returns>The value associated with the specified key.</returns>
        public virtual T Get<T>(string key)
        {
            return (T)Cache[key];
        }

        /// <summary>
        /// Adds the specified key and object to the cache.
        /// </summary>
        /// <param name="key">key</param>
        /// <param name="data">Data</param>
        /// <param name="cacheTime">Cache time</param>
        public virtual void Set(string key, object data, int cacheTime)
        {
            if (data == null)
                return;

            var policy = new CacheItemPolicy();
            policy.AbsoluteExpiration = DateTime.Now + TimeSpan.FromMinutes(cacheTime);
            Cache.Add(new CacheItem(key, data), policy);
        }

        /// <summary>
        /// Gets a value indicating whether the value associated with the specified key is cached
        /// </summary>
        /// <param name="key">key</param>
        /// <returns>Result</returns>
        public virtual bool IsSet(string key)
        {
            return (Cache.Contains(key));
        }

        /// <summary>
        /// Removes the value with the specified key from the cache
        /// </summary>
        /// <param name="key">/key</param>
        public virtual void Remove(string key)
        {
            Cache.Remove(key);
        }

        /// <summary>
        /// Removes items by pattern
        /// </summary>
        /// <param name="pattern">pattern</param>
        public virtual void RemoveByPattern(string pattern)
        {
            var regex = new Regex(pattern, RegexOptions.Singleline | RegexOptions.Compiled | RegexOptions.IgnoreCase);
            var keysToRemove = new List<String>();

            foreach (var item in Cache)
                if (regex.IsMatch(item.Key))
                    keysToRemove.Add(item.Key);

            foreach (string key in keysToRemove)
            {
                Remove(key);
            }
        }

        /// <summary>
        /// Clear all cache data
        /// </summary>
        public virtual void Clear()
        {
            foreach (var item in Cache)
                Remove(item.Key);
        }
    }

Review this NopCommerce link for more details. Register ICacheManager in Unity to create object for MemoryCacheManager and use it in your application. Happy coding :)