/**
* @ 创建单个对象的SQL类型的缓存策略，该方法适用于单个字段类型对象
* @ T 要创建的缓存对象类型，仅限单个类型
* @ key 缓存的键
* @ dbConnectionStr 数据库连接字符串
* @ cmdText sql语句，必须包含架构信息，并且不能使用“*”号代替要查询的字段
* @ offset 缓存过期时间
* @ sourceChange 数据源更改通知事件
* @ priority 缓存逐出的优先级
* */
public static CacheItem CreateSQLCache(string key, string dbConnectionStr, string cmdText, DateTimeOffset offset, EventHandler sourceChange, CacheItemPriority priority = CacheItemPriority.Default)
{
SqlCacheExpiration sqlCache = GetSqlCache(key, dbConnectionStr, cmdText, offset, sourceChange);
CacheItem cacheItem = null;
CacheItemPolicy policy = null;
cacheItem = sqlCache.CreateSQLCacheScalar(key, cmdText, offset, out policy, priority);
Cache.Set(cacheItem, policy);
return(cacheItem);
}
/**
* @ 创建SQL类型的缓存策略
* @ T 要创建的缓存对象类型，仅限单个类型
* @ key 缓存的键
* @ dbConnectionStr 数据库连接字符串
* @ cmdText sql语句，必须包含架构信息，并且不能使用“*”号代替要查询的字段
* @ offset 缓存过期时间
* @ sourceChange 数据源更改通知事件
* @ cacheType 缓存类型
* @ priority 缓存逐出的优先级
* */
public static CacheItem CreateSQLCache <T>(string key, string dbConnectionStr, string cmdText, DateTimeOffset offset, EventHandler sourceChange, SqlCacheOption cacheType, CacheItemPriority priority = CacheItemPriority.Default) where T : class, new()
{
SqlCacheExpiration sqlCache = GetSqlCache(key, dbConnectionStr, cmdText, offset, sourceChange);
CacheItem cacheItem = null;
CacheItemPolicy policy = null;
switch (cacheType)
{
case SqlCacheOption.Single:
cacheItem = sqlCache.CreateSQLCacheSingle <T>(key, cmdText, offset, out policy, priority);
break;
case SqlCacheOption.List:
cacheItem = sqlCache.CreateSQLCacheList <T>(key, cmdText, offset, out policy, priority);
break;
}
Cache.Set(cacheItem, policy);
return(cacheItem);
}
/**
* @ 创建 SqlCacheExpiration 对象
* @ T 要创建的缓存对象类型，仅限单个类型
* @ key 缓存的键
* @ dbConnectionStr 数据库连接字符串
* @ cmdText sql语句，必须包含架构信息，并且不能使用“*”号代替要查询的字段
* @ offset 缓存过期时间
* @ sourceChange 数据源更改通知事件
* */
private static SqlCacheExpiration GetSqlCache(string key, string dbConnectionStr, string cmdText, DateTimeOffset offset, EventHandler sourceChange)
{
if (string.IsNullOrEmpty(dbConnectionStr))
{
throw new ArgumentNullException("dbConnectionStr不能为空");
}
if (string.IsNullOrEmpty(cmdText))
{
throw new ArgumentNullException("cmdText不能为空");
}
SqlCacheExpiration sqlCache = new SqlCacheExpiration(dbConnectionStr);
sqlCache.SourceChange += delegate(object sender, EventArgs e)
{
if (sourceChange != null)
{
sourceChange(sender, e);
}
};
return(sqlCache);
}