个人项目框架搭建 -- 缓存接口与实现

1、缓存接口

using System;
using System.Collections.Generic;
using System.Runtime.Caching;
using System.Text.RegularExpressions;

namespace EnterpriseFrame.Core.Caching
{
    /// <summary>
    /// Represents a manager for caching between HTTP requests (long term caching)
    /// </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);
        }
    }
}

2、扩展

using System;

namespace EnterpriseFrame.Core.Caching
{
    /// <summary>
    /// Extensions
    /// </summary>
    public static class CacheExtensions
    {
        /// <summary>
        /// 获取缓存，不存在则将acquire的结果存入缓存，默认时间60分钟
        /// </summary>
        /// <typeparam name="T">Type</typeparam>
        /// <param name="cacheManager">Cache manager</param>
        /// <param name="key">Cache key</param>
        /// <param name="acquire">Function to load item if it's not in the cache yet</param>
        /// <returns>Cached item</returns>
        public static T Get<T>(this ICacheManager cacheManager, string key, Func<T> acquire)
        {
            return Get(cacheManager, key, 60, acquire);
        }

        /// <summary>
        /// 获取缓存,如果不存在缓存中，执行结果然后将其加载和缓存
        /// </summary>
        /// <typeparam name="T">缓存类型</typeparam>
        /// <param name="cacheManager">Cache manager</param>
        /// <param name="key">Cache key</param>
        /// <param name="cacheTime">缓存时间 在0分钟-不要缓存</param>
        /// <param name="acquire">没有缓存则执行此表达式设置缓存</param>
        /// <returns>Cached item</returns>
        public static T Get<T>(this ICacheManager cacheManager, string key, int cacheTime, Func<T> acquire) 
        {
            if (cacheManager.IsSet(key))
            {
                return cacheManager.Get<T>(key);
            }
            else
            {
                var result = acquire();
                if (cacheTime > 0)
                    cacheManager.Set(key, result, cacheTime);
                return result;
            }
        }
    }
}

3、MemoryCacheManager实现

using System;
using System.Collections.Generic;
using System.Runtime.Caching;
using System.Text.RegularExpressions;

namespace EnterpriseFrame.Core.Caching
{
    /// <summary>
    /// Represents a manager for caching between HTTP requests (long term caching)
    /// </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);
        }
    }
}

摘自：NopCommerce框架(http://nopcommerce.codeplex.com/)