.net简单的缓存类

拼搏现实的明天。 2022-08-10 12:44 116阅读 0赞

接着[上一篇][Link 1]内容，下面处理webapi宿主到windows服务中时，简单的缓存类处理：

using System;
    using System.Collections;
    using System.Web;
    using System.Web.Caching;
    
    namespace aaaaa.Api.Business
    {
        /// <summary>
        /// 缓存类
        /// </summary>
        public class CacheHelper
        {
            /// <summary>
            /// 增加一个缓存对象
            /// </summary>
            /// <param name="strKey">键值名称</param>
            /// <param name="valueObj">被缓存对象</param>
            /// <param name="durationMin">缓存失效时间（默认为5分钟）</param>
            /// <param name="cachePriority">保留优先级(枚举数值)</param>
            /// <returns>缓存写入是否成功true 、false</returns>
            public static bool InsertCach(string strKey, object valueObj, int durationMin,
                CacheItemPriority cachePriority = CacheItemPriority.Default)
            {
                TimeSpan ts;
                if (!string.IsNullOrWhiteSpace(strKey) && valueObj != null)
                {
                    //onRemove是委托执行的函数，具体方法看下面的onRemove(...)
                    CacheItemRemovedCallback callBack = new CacheItemRemovedCallback(onRemove);
                    ts = durationMin == 0 ? new TimeSpan(0, 5, 0) : new TimeSpan(0, durationMin, 0);
                    //HttpContext.Current.Cache.Insert(
                    HttpRuntime.Cache.Insert(
                        strKey,
                        valueObj,
                        null,
                        DateTime.Now.Add(ts),
                        Cache.NoSlidingExpiration,
                        cachePriority,
                        callBack
                    );
                    return true;
                }
                else
                {
                    return false;
                }
            }
    
            /// <summary>
            /// 判断缓存对象是否存在
            /// </summary>
            /// <param name="strKey">缓存键值名称</param>
            /// <returns>是否存在true 、false</returns>
            public static bool IsExist(string strKey)
            {
                //return HttpContext.Current.Cache[strKey] != null;
                return HttpRuntime.Cache.Get(strKey) != null;
            }
    
            /// <summary>
            /// 读取缓存对象
            /// </summary>
            /// <param name="strKey">缓存键值名称</param>
            /// <returns>缓存对象，objec类型</returns>
            public static object GetCache(string strKey)
            {
                //if (HttpContext.Current.Cache[strKey] != null)
                if (IsExist(strKey))
                {
                    object obj = HttpRuntime.Cache.Get(strKey);
                    return obj ?? null;
                }
                else
                {
                    return null;
                }
            }
    
            /// <summary>
            /// 移除缓存对象
            /// </summary>
            /// <param name="strKey">缓存键值名称</param>
            public static void Remove(string strKey)
            {
                //if (HttpContext.Current.Cache[strKey] != null)
                if (IsExist(strKey))
                {
                    HttpRuntime.Cache.Remove(strKey);
                }
            }
    
            /// <summary>
            /// 清除所有缓存
            /// </summary>
            public static void Clear()
            {
                IDictionaryEnumerator enu = HttpRuntime.Cache.GetEnumerator();
                while (enu.MoveNext())
                {
                    Remove(enu.Key.ToString());
                }
            }
    
            public static CacheItemRemovedReason reason;
            /// <summary>
            /// 此方法在值失效之前调用，可以用于在失效之前更新数据库，或从数据库重新获取数据
            /// </summary>
            /// <param name="strKey"></param>
            /// <param name="obj"></param>
            /// <param name="reason"></param>
            private static void onRemove(string strKey, object obj, CacheItemRemovedReason r)
            {
                reason = r;
            }
    
            //...
    
        }
    }

[Link 1]: http://blog.csdn.net/joyhen/article/details/40379099