absolutetime.cs

HeyCacher 高性能缓存方案(带源码) 1. 文件的所有权益归上传用户所有 2. 未经权益所有人同意不得将文件中的内容挪作商业或盈利用途 3. CSDN下载频道仅提供交流平台

//===============================================================================
// CSDN HeyCache 
//===============================================================================
// 修改记录：[按最后修改时间倒排序]
// 2007.06.11 by tangwei
//
// 代码来源：参考于dotnet企业库3.0版
//===============================================================================

using System;
using System.Globalization;
using System.Runtime.Serialization;
using System.Security.Permissions;
using Microsoft.Practices.EnterpriseLibrary.Caching.Properties;

namespace HeyCacher.Components.Expirations
{
    /// <summary>
    ///	以绝对时间为依赖的过期策略
    /// </summary>
    [Serializable]    
    public class AbsoluteTime : ICacheItemExpiration
    {
        public DateTime AbsoluteExpirationTime
        {
            get { return absoluteExpirationTime; }
        }
        private DateTime absoluteExpirationTime;

        public AbsoluteTime(){ }
        public AbsoluteTime(TimeSpan timeFromNow)
        {
            innerCreate(DateTime.Now + timeFromNow);
        }
        public AbsoluteTime(DateTime absoluteTime)
        {
            innerCreate(absoluteTime);
        }

        public void Create(params string[] Params)
        {
            innerCreate(DateTime.Parse(Params[0]));
        }
        private void innerCreate(DateTime absoluteTime)
        {
            if (absoluteTime > DateTime.Now)
            {
                // Convert to UTC in order to compensate for time zones
                this.absoluteExpirationTime = absoluteTime.ToUniversalTime();
            }
            else
            {
                throw new ArgumentOutOfRangeException("absoluteTime", Resources.ExceptionRangeAbsoluteTime);
            }
        }
		
        public bool HasExpired()
        {
            // Convert to UTC in order to compensate for time zones		
            DateTime nowDateTime = DateTime.Now.ToUniversalTime();

            // Check expiration
            return nowDateTime.Ticks >= this.absoluteExpirationTime.Ticks;
        }
        public void Notify()
        {
        }
        public void Initialize(ExpirationItem owningCacheItem)
        {
        }        
    }
}