• .net core MemoryCache缓存


    /// <summary>
        /// 缓存帮助类
        /// </summary>
        public class MemoryCacheHelper
        {
            private static readonly MemoryCache Cache = new MemoryCache(new MemoryCacheOptions());
    
            /// <summary>
            /// 验证缓存项是否存在
            /// </summary>
            /// <param name="key">缓存Key</param>
            /// <returns></returns>
            public static bool Exists(string key)
            {
                if (key == null)
                    throw new ArgumentNullException(nameof(key));
                return Cache.TryGetValue(key, out _);
            }
    
            /// <summary>
            /// 添加缓存
            /// </summary>
            /// <param name="key">缓存Key</param>
            /// <param name="value">缓存Value</param>
            /// <param name="expiresSliding">滑动过期时长(如果在过期时间内有操作,则以当前时间点延长过期时间)</param>
            /// <param name="expiressAbsoulte">绝对过期时长</param>
            /// <returns></returns>
            public static bool Set(string key, object value, TimeSpan expiresSliding, TimeSpan expiressAbsoulte)
            {
                if (key == null)
                    throw new ArgumentNullException(nameof(key));
                if (value == null)
                    throw new ArgumentNullException(nameof(value));
    
                Cache.Set(key, value,
                    new MemoryCacheEntryOptions().SetSlidingExpiration(expiresSliding)
                        .SetAbsoluteExpiration(expiressAbsoulte));
                return Exists(key);
            }
    
            /// <summary>
            /// 添加缓存
            /// </summary>
            /// <param name="key">缓存Key</param>
            /// <param name="value">缓存Value</param>
            /// <param name="expiresIn">缓存时长</param>
            /// <param name="isSliding">是否滑动过期(如果在过期时间内有操作,则以当前时间点延长过期时间)</param>
            /// <returns></returns>
            public static bool Set(string key, object value, TimeSpan expiresIn, bool isSliding = false)
            {
                if (key == null)
                    throw new ArgumentNullException(nameof(key));
                if (value == null)
                    throw new ArgumentNullException(nameof(value));
    
                Cache.Set(key, value,
                    isSliding
                        ? new MemoryCacheEntryOptions().SetSlidingExpiration(expiresIn)
                        : new MemoryCacheEntryOptions().SetAbsoluteExpiration(expiresIn));
    
                return Exists(key);
            }
    
            #region 删除缓存
    
            /// <summary>
            /// 删除缓存
            /// </summary>
            /// <param name="key">缓存Key</param>
            /// <returns></returns>
            public static void Remove(string key)
            {
                if (key == null)
                    throw new ArgumentNullException(nameof(key));
    
                Cache.Remove(key);
            }
    
            /// <summary>
            /// 批量删除缓存
            /// </summary>
            /// <returns></returns>
            public static void RemoveAll(IEnumerable<string> keys)
            {
                if (keys == null)
                    throw new ArgumentNullException(nameof(keys));
    
                keys.ToList().ForEach(item => Cache.Remove(item));
            }
            #endregion
    
            #region 获取缓存
    
            /// <summary>
            /// 获取缓存
            /// </summary>
            /// <param name="key">缓存Key</param>
            /// <returns></returns>
            public static T Get<T>(string key) where T : class
            {
                if (key == null)
                    throw new ArgumentNullException(nameof(key));
    
                return Cache.Get(key) as T;
            }
    
            /// <summary>
            /// 获取缓存
            /// </summary>
            /// <param name="key">缓存Key</param>
            /// <returns></returns>
            public static object Get(string key)
            {
                if (key == null)
                    throw new ArgumentNullException(nameof(key));
    
                return Cache.Get(key);
            }
    
            /// <summary>
            /// 获取缓存集合
            /// </summary>
            /// <param name="keys">缓存Key集合</param>
            /// <returns></returns>
            public static IDictionary<string, object> GetAll(IEnumerable<string> keys)
            {
                if (keys == null)
                    throw new ArgumentNullException(nameof(keys));
    
                var dict = new Dictionary<string, object>();
                keys.ToList().ForEach(item => dict.Add(item, Cache.Get(item)));
                return dict;
            }
            #endregion
    
            /// <summary>
            /// 删除所有缓存
            /// </summary>
            public static void RemoveCacheAll()
            {
                var l = GetCacheKeys();
                foreach (var s in l)
                {
                    Remove(s);
                }
            }
    
            /// <summary>
            /// 删除匹配到的缓存
            /// </summary>
            /// <param name="pattern"></param>
            /// <returns></returns>
            public static void RemoveCacheRegex(string pattern)
            {
                IList<string> l = SearchCacheRegex(pattern);
                foreach (var s in l)
                {
                    Remove(s);
                }
            }
    
            /// <summary>
            /// 搜索 匹配到的缓存
            /// </summary>
            /// <param name="pattern"></param>
            /// <returns></returns>
            public static IList<string> SearchCacheRegex(string pattern)
            {
                var cacheKeys = GetCacheKeys();
                var l = cacheKeys.Where(k => Regex.IsMatch(k, pattern)).ToList();
                return l.AsReadOnly();
            }
    
            /// <summary>
            /// 获取所有缓存键
            /// </summary>
            /// <returns></returns>
            public static List<string> GetCacheKeys()
            {
                const BindingFlags flags = BindingFlags.Instance | BindingFlags.NonPublic;
                var entries = Cache.GetType().GetField("_entries", flags).GetValue(Cache);
                var cacheItems = entries as IDictionary;
                var keys = new List<string>();
                if (cacheItems == null) return keys;
                foreach (DictionaryEntry cacheItem in cacheItems)
                {
                    keys.Add(cacheItem.Key.ToString());
                }
                return keys;
            }
    
        }
  • 相关阅读:
    IEEE Bigger系列题解
    Codeforces Round #354 (Div. 2) E. The Last Fight Between Human and AI 数学
    Codeforces Round #354 (Div. 2) D. Theseus and labyrinth bfs
    Codeforces Round #354 (Div. 2) C. Vasya and String 二分
    Codeforces Round #354 (Div. 2) B. Pyramid of Glasses 模拟
    Codeforces Round #354 (Div. 2) A. Nicholas and Permutation 水题
    Codeforces Round #FF (Div. 1) B. DZY Loves Modification 优先队列
    Codeforces Round #FF (Div. 1) A. DZY Loves Sequences 动态规划
    2016 UESTC DP专题题解
    HDU 5701 中位数计数 暴力
  • 原文地址:https://www.cnblogs.com/li-lun/p/9618565.html
Copyright © 2020-2023  润新知