C# Cache缓存读取设置

先创建一个CacheHelper.cs类，代码如下：

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

public class CacheHelper
{
    /// <summary>
    /// 获取数据缓存
    /// </summary>
    /// <param name="cacheKey">键</param>
    public static object GetCache(string cacheKey)
    {
        var objCache = HttpRuntime.Cache.Get(cacheKey);
        return objCache;
    }
    /// <summary>
    /// 设置数据缓存
    /// </summary>
    public static void SetCache(string cacheKey, object objObject)
    {
        var objCache = HttpRuntime.Cache;
        objCache.Insert(cacheKey, objObject);
    }
    /// <summary>
    /// 设置数据缓存
    /// </summary>
    public static void SetCache(string cacheKey, object objObject, int timeout = 7200)
    {
        try
        {
            if (objObject == null) return;
            var objCache = HttpRuntime.Cache;
            //相对过期
            //objCache.Insert(cacheKey, objObject, null, DateTime.MaxValue, timeout, CacheItemPriority.NotRemovable, null);
            //绝对过期时间
            objCache.Insert(cacheKey, objObject, null, DateTime.Now.AddSeconds(timeout), TimeSpan.Zero, CacheItemPriority.High, null);
        }
        catch (Exception)
        {
            //throw;
        }
    }
    /// <summary>
    /// 移除指定数据缓存
    /// </summary>
    public static void RemoveAllCache(string cacheKey)
    {
        var cache = HttpRuntime.Cache;
        cache.Remove(cacheKey);
    }
    /// <summary>
    /// 移除全部缓存
    /// </summary>
    public static void RemoveAllCache()
    {
        var cache = HttpRuntime.Cache;
        var cacheEnum = cache.GetEnumerator();
        while (cacheEnum.MoveNext())
        {
            cache.Remove(cacheEnum.Key.ToString());
        }
    }
}

然后是调用：

        public IEnumerable<CompanyModel> FindCompanys()
        {
            var cache = CacheHelper.GetCache("commonData_Company");//先读取
            if (cache == null)//如果没有该缓存
            {
                var queryCompany = _base.CompanyModel();//从数据库取出
                var enumerable = queryCompany.ToList();
                CacheHelper.SetCache("commonData_Company", enumerable);//添加缓存
                return enumerable;
            }
            var result = (List<CompanyModel>)cache;//有就直接返回该缓存
            return result;
        }

　测试结果：

首次加载进来是为null，然后读取数据库，添加进缓存，当前返回前台的是从数据库中取出的数据。

刷新页面，发现缓存中已经有了读出的30条数据，

然后接下来走，返回缓存中的数据：