通用的webCache
public static class WebCache
{
/// <summary>
/// 一般配置Cache过期时间，秒钟计
/// </summary>
/// <value>The common cache time out.</value>
public static int CommonCacheTimeOut
{
get
{
if (_CommonCacheTimeOut == null)
{
string settings = ConfigurationManager.AppSettings["CommonCacheTimeOut"];
int timeOut;
if (!int.TryParse(settings, out timeOut))
timeOut = 10; //默认10分钟过期
_CommonCacheTimeOut = timeOut;
}
return _CommonCacheTimeOut.Value;
}
}
private static int? _CommonCacheTimeOut;
/// <summary>
/// 查询配置Chche过期时间，秒钟计
/// </summary>
/// <value>The query cache time out.</value>
public static int QueryCacheTimeOut
{
get
{
if (_QueryCacheTimeOut == null)
{
string settings = ConfigurationManager.AppSettings["QueryCacheTimeOut"];
int timeOut;
if (!int.TryParse(settings, out timeOut))
timeOut = 10; //默认10秒钟过期
_QueryCacheTimeOut = timeOut;
}
return _QueryCacheTimeOut.Value;
}
}
private static int? _QueryCacheTimeOut;
/// <summary>
/// Cache插入锁
/// </summary>
private static object CacheLocker = new object();
/// <summary>
/// 获取缓存的对象。当没有缓存的时候，自动创建对象并进行缓存。只支持引用类型的缓存。
/// </summary>
/// <typeparam name="T"></typeparam>
/// <param name="key">The key.</param>
/// <param name="timeOut">单位：秒</param>
/// <param name="onCreateInstance">The on create instance.</param>
/// <returns></returns>
public static T GetCachedObject<T>(string key, int timeOut, Func<T> onCreateInstance)
{
if (timeOut > 0)
{
//当前Cache对象
System.Web.Caching.Cache webCache = System.Web.HttpRuntime.Cache;
//获取缓存的对象
T cachedObject = (T)webCache.Get(key);
if (null == cachedObject)
{
//加锁确保多线程安全
lock (CacheLocker)
{
cachedObject = (T)webCache.Get(key);
if (null == cachedObject)
{
//创建新的对象
cachedObject = onCreateInstance();
//将创建的对象进行缓存
if (cachedObject != null)
webCache.Insert(key, cachedObject, null, DateTime.Now.AddSeconds(timeOut), System.Web.Caching.Cache.NoSlidingExpiration);
}
}
}
return cachedObject;
}
else
{
//不设置缓存，则创建新的对象
return onCreateInstance();
}
}
/// <summary>
/// 获取缓存的对象。当没有缓存的时候，自动创建对象并进行缓存。只支持引用类型的缓存。
/// </summary>
/// <typeparam name="T"></typeparam>
/// <param name="key">The key.</param>
/// <param name="onCreateInstance">The on create instance.</param>
/// <returns></returns>
public static T GetCachedObject<T>(string key, Func<T> onCreateInstance)
{
return GetCachedObject<T>(key, CommonCacheTimeOut, onCreateInstance);
}
/// <summary>
/// 获取缓存的查询。当没有缓存的时候，自动创建对象并进行缓存。只支持引用类型的缓存。
/// </summary>
/// <typeparam name="T"></typeparam>
/// <param name="key">The key.</param>
/// <param name="onCreateInstance">The on create instance.</param>
/// <returns></returns>
public static T GetCachedQuery<T>(string key, Func<T> onCreateInstance)
{
return GetCachedObject<T>(key, QueryCacheTimeOut, onCreateInstance);
}
/// <summary>
/// 移除缓存的对象
/// </summary>
/// <param name="key">The key.</param>
/// <returns></returns>
public static object Remove(string key)
{
//当前Cache对象
System.Web.Caching.Cache webCache = System.Web.HttpRuntime.Cache;
lock (CacheLocker)
{
return webCache.Remove(key);
}
}
/// <summary>
/// 清除所有缓存
/// </summary>
public static void RemoveAll()
{
IDictionaryEnumerator cacheEnum = System.Web.HttpRuntime.Cache.GetEnumerator();
while (cacheEnum.MoveNext())
{
System.Web.HttpRuntime.Cache.Remove(cacheEnum.Key.ToString());
}
}
}
如何调用呢？
/// <summary>
/// 获取新闻内容
/// </summary>
/// <param name="articleID"></param>
/// <param name="token"></param>
/// <param name="mode"></param>
/// <returns></returns>
public static ArticleInfoEntity GetCachedArticleInfo(long articleID, string token, int mode)
{
string key = "GetArticleInfo_" + articleID;
return
WebCache.GetCachedObject<ArticleInfoEntity>(key, InterfaceHelper.ContentCacheTime,
delegate()
{
ArticleInfoEntity articleInfo;
int iUseXml = ConfigurationManager.AppSettings["UseStaticContent"] != null ? Convert.ToInt32(ConfigurationManager.AppSettings["UseStaticContent"]) : 0;
if ( 1 == iUseXml ) //直接读xml
{
articleInfo = GetArticleInfoByFile(articleID);
}
else //尝试先读数据库
{
//DB Error
if (InterfaceHelper.CheckDBError())
{
articleInfo = GetArticleInfoByFile(articleID);
}
else
{
try
{
articleInfo = GetArticleInfo(articleID, token, mode);
//DB OK
InterfaceHelper.SetDBTrue();
}
//DB Error
catch (SqlException ex)
{
InterfaceHelper.SetDBError();
articleInfo = GetArticleInfoByFile(articleID);
ExceptionHandler.Instance.HandleExceptionEx(ex);
}
}
}
return articleInfo;
});
}
