Cache Helper类

Posted 2020-08-20 晓明的哥哥

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

namespace DMSite.Common
{
    /// <summary>
    /// 服务器缓存帮助类
    /// </summary>
    public class CacheHelper
    {
        /// <summary>
        /// 创建缓存项的文件依赖
        /// </summary>
        /// <param name="key">缓存Key</param>
        /// <param name="obj">object对象</param>
        /// <param name="fileName">文件绝对路径</param>
        public static void InsertFile(string key, object obj, string fileName)
        {
            //创建缓存依赖项
            CacheDependency dep = new CacheDependency(fileName);
            //创建缓存
            HttpRuntime.Cache.Insert(key, obj, dep);
        }

        /// <summary>
        /// 创建缓存项过期
        /// </summary>
        /// <param name="key">缓存Key</param>
        /// <param name="obj">object对象</param>
        public static void Insert(string key, object obj)
        {
            if (obj != null)
            {
                if (IsExist(key))
                {
                    HttpRuntime.Cache[key] = obj;
                }
                else
                {
                    int expires = ConvertHelper.ToInt(ConfigHelper.GetAppSettings("TimeCache"));
                    HttpRuntime.Cache.Insert(key, obj, null, System.Web.Caching.Cache.NoAbsoluteExpiration, new TimeSpan(0, expires, 0));
                }
                
            }
        }
        /// <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 HttpRuntime.Cache[strKey] != null;
        }
        /// <summary>
        /// 获取缓存对象
        /// </summary>
        /// <param name="key">缓存Key</param>
        /// <returns>object对象</returns>
        public static object GetCache(string key)
        {
            if (string.IsNullOrEmpty(key))
                return null;
            if (ConfigHelper.GetAppSettings("IsCache") == "false")
            {
                return null;
            }

            return HttpRuntime.Cache.Get(key);
        }

        /// <summary>
        /// 获取缓存对象
        /// </summary>
        /// <typeparam name="T">T对象</typeparam>
        /// <param name="key">缓存Key</param>
        /// <returns></returns>
        public static T Get<T>(string key)
        {
            object obj = GetCache(key);
            return obj == null ? default(T) : (T)obj;
        }

        /// <summary>
        /// 移除指定数据缓存
        /// </summary>
        public static void RemoveCache(string CacheKey)
        {
            System.Web.Caching.Cache _cache = HttpRuntime.Cache;
            _cache.Remove(CacheKey);
        }

        /// <summary>
        /// 移除全部缓存
        /// </summary>
        public static void RemoveAllCache()
        {
            System.Web.Caching.Cache _cache = HttpRuntime.Cache;
            IDictionaryEnumerator CacheEnum = _cache.GetEnumerator();
            while (CacheEnum.MoveNext())
            {
                _cache.Remove(CacheEnum.Key.ToString());
            }
        }
    }
}