/// <summary>
/// 设置缓存项的值。
/// </summary>
/// <param name="key">缓存项的原始键值。</param>
/// <param name="value">缓存项的值。</param>
/// <param name="methodName">调用当前的方法的方法名称。</param>
/// <param name="expiration">缓存项的过期信息实例对象：<c>null</c> 表示滑动十分钟过期。</param>
protected void SetValue(string key, object value, string methodName, Expiration expiration)
{
if (ReferenceEquals(key, null))
{
throw new ArgumentNullException("[BaseCacheContainer].[SetValue].key");
}
if (ReferenceEquals(value, null))
{
return;
}
expiration = expiration ?? Expiration.CreateInstance();
if (expiration.Container != null && !ReferenceEquals(expiration.Container, this))
{
throw new ArgumentException("[BaseCacheContainer].[SetValue].expiration.Container 已存在，不能添加！");
}
expiration.Container = this;
var notification = expiration.Notification ?? CacheNotification.CreateInstance();
notification.Key = key;
notification.SetValue(value, false);
if (notification.Expiration != null && !ReferenceEquals(notification.Expiration, expiration))
{
throw new ArgumentException("[BaseCacheContainer].[SetValue].expiration.[Notification].Expiration 已存在，过期对象处理错误！");
}
notification.Expiration = expiration;
Push(GetKey(key), methodName, expiration);
}
/// <summary>
/// 将缓存项保存到缓存容器中。
/// </summary>
/// <param name="cacheItemKey">用于缓存项的键名称。</param>
/// <param name="methodName">用户调用的原始方法名称：Add 或者 Update</param>
/// <param name="expiration">与之关联的缓存过期信息。</param>
protected override void Push(string cacheItemKey, string methodName, Expiration expiration)
{
var absoluteExpiration = !expiration.AutoDelay ? expiration.DeadTime : Cache.NoAbsoluteExpiration;
var slidingExpiration = expiration.AutoDelay ? (expiration.DeadTime - expiration.InitialTime) : Cache.NoSlidingExpiration;
if (methodName == "Add")
{
var obj = _cache.Add(cacheItemKey, expiration.Notification.Value, null, absoluteExpiration, slidingExpiration, CacheItemPriority.Normal, null);
if (!ReferenceEquals(obj, null))
{
throw new InvalidOperationException(string.Format("已存在相同键【{0}】的项！", expiration.Notification.Key));
}
}
else
{
_cache.Insert(cacheItemKey, expiration.Notification.Value, null, absoluteExpiration, slidingExpiration, CacheItemPriority.Normal, null);
}
expiration.Notification.SetValue(CacheNotification.DefaultValue, false);
}
/// <summary> /// 将缓存项保存到缓存容器中。 /// </summary> /// <param name="cacheItemKey">用于缓存项的键名称。</param> /// <param name="methodName">用户调用的原始方法名称：Add 或者 Update</param> /// <param name="expiration">与之关联的缓存过期信息。</param> protected abstract void Push(string cacheItemKey, string methodName, Expiration expiration);
/// <summary>
/// 更新指定键的值。
/// </summary>
/// <param name="key">缓存项的键。</param>
/// <param name="value">缓存项新的值。</param>
/// <param name="expiration">缓存项的过期设置信息：<c>null</c> 表示滑动十分钟过期。</param>
public void Update(string key, object value, Expiration expiration = null)
{
SetValue(key, value, "Update", expiration);
}
/// <summary>
/// 向缓存容器中添加一个新的项。
/// </summary>
/// <param name="key">缓存项的键。</param>
/// <param name="value">待缓存的值。</param>
/// <param name="expiration">缓存项的过期设置信息，<c>null</c> 表示滑动十分钟过期。</param>
public void Add(string key, object value, Expiration expiration = null)
{
SetValue(key, value, "Add", expiration);
}
/// <summary>
/// 根据指定键获取或添加指定值。
/// </summary>
/// <typeparam name="TResult">缓存容器值的强类型表示。</typeparam>
/// <param name="container">一个缓存容器接口的实例对象。</param>
/// <param name="key">缓存项的键。</param>
/// <param name="newValue">获取失败后待添加的新值。</param>
/// <param name="expiration">缓存项的过期设置信息：<c>null</c> 表示使用缺省的过期设置。</param>
/// <returns>获取得到的缓存项的值。</returns>
/// <exception cref="System.ArgumentNullException">container or key or newValue</exception>
public static TResult GetOrAddX <TResult>(this ICacheContainer container, string key, TResult newValue, Expiration expiration = null)
{
if (ReferenceEquals(container, null))
{
throw new ArgumentNullException(string.Format("[ICacheContainerExtensions].[GetOrAddX<{0}>].container", typeof(TResult).FullName));
}
if (key == null)
{
throw new ArgumentNullException(string.Format("[ICacheContainerExtensions].[GetOrAddX<{0}>].key", typeof(TResult).FullName));
}
if (newValue == null)
{
throw new ArgumentNullException(string.Format("[ICacheContainerExtensions].[GetOrAddX<{0}>].newValue", typeof(TResult).FullName));
}
object value = null;
if (container.TryGetValue(key, out value))
{
return((TResult)value);
}
container.Update(key, newValue, expiration);
return(newValue);
}
/// <summary>
/// 根据指定键获取或添加指定值。
/// </summary>
/// <param name="container">一个缓存容器接口的实例对象。</param>
/// <param name="key">缓存项的键。</param>
/// <param name="newValue">获取失败后待添加的新值。</param>
/// <param name="expiration">缓存项的过期设置信息：<c>null</c> 表示使用缺省的过期设置。</param>
/// <returns>获取得到的缓存项的值。</returns>
/// <exception cref="System.ArgumentNullException">container or key or newValue</exception>
public static object GetOrAdd(this ICacheContainer container, string key, object newValue, Expiration expiration = null)
{
if (ReferenceEquals(container, null))
{
throw new ArgumentNullException("[ICacheContainerExtensions].[GetOrAdd].container");
}
if (key == null)
{
throw new ArgumentNullException("[ICacheContainerExtensions].[GetOrAdd].key");
}
object value = null;
if (container.TryGetValue(key, out value))
{
return(value);
}
container.Update(key, newValue, expiration);
return(newValue);
}
