/// <summary>
/// 安全地获取缓存容器中的值。
/// </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="defaultValue">获取失败后，要返回的缺省值。</param>
/// <param name="throwIfException">如果设置为 <c>true</c> 表示错误后抛出异常。</param>
/// <returns>获取得到的缓存项的值。</returns>
/// <exception cref="System.ArgumentNullException">container or key</exception>
public static TResult GetValueX <TResult>(this ICacheContainer container, string key, TResult defaultValue = default(TResult), bool throwIfException = true)
{
if (ReferenceEquals(container, null))
{
throw new ArgumentNullException(string.Format("[ICacheContainerExtensions].[GetValueX<{0}>].container", typeof(TResult).FullName));
}
if (key == null)
{
throw new ArgumentNullException(string.Format("[ICacheContainerExtensions].[GetValueX<{0}>].key", typeof(TResult).FullName));
}
try
{
object value = null;
if (container.TryGetValue(key, out value))
{
return((TResult)value);
}
return(defaultValue);
}
catch
{
if (throwIfException)
{
throw;
}
else
{
return(defaultValue);
}
}
}
/// <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="newValueFunc">获取失败后待添加的新值委托。</param>
/// <returns>获取得到的缓存项的值。</returns>
/// <exception cref="System.ArgumentNullException">container or key or
/// newValueFunc</exception>
public static TResult GetOrAddXWithFunc <TResult>(this ICacheContainer container, string key, Func <Tuple <TResult, Expiration> > newValueFunc)
{
if (ReferenceEquals(container, null))
{
throw new ArgumentNullException(string.Format("[ICacheContainerExtensions].[GetOrAddXWithFunc<{0}>].container", typeof(TResult).FullName));
}
if (key == null)
{
throw new ArgumentNullException(string.Format("[ICacheContainerExtensions].[GetOrAddXWithFunc<{0}>].key", typeof(TResult).FullName));
}
if (newValueFunc == null)
{
throw new ArgumentNullException(string.Format("[ICacheContainerExtensions].[GetOrAddXWithFunc<{0}>].newValueFunc", typeof(TResult).FullName));
}
object value = null;
if (container.TryGetValue(key, out value))
{
return((TResult)value);
}
var newValue = newValueFunc();
container.Update(key, newValue.Item1, newValue.Item2);
return(newValue.Item1);
}
/// <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="newValueFunc">获取失败后待添加的新值委托。</param>
/// <returns>获取得到的缓存项的值。</returns>
/// <exception cref="System.ArgumentNullException">container or key or
/// newValueFunc</exception>
public static object GetOrAddWithFunc(this ICacheContainer container, string key, Func <Tuple <object, Expiration> > newValueFunc)
{
if (ReferenceEquals(container, null))
{
throw new ArgumentNullException("[ICacheContainerExtensions].[GetOrAddWithFunc].container");
}
if (key == null)
{
throw new ArgumentNullException("[ICacheContainerExtensions].[GetOrAddWithFunc].key");
}
if (newValueFunc == null)
{
throw new ArgumentNullException("[ICacheContainerExtensions].[GetOrAddWithFunc].newValueFunc");
}
object value = null;
if (container.TryGetValue(key, out value))
{
return(value);
}
var newValue = newValueFunc();
container.Update(key, newValue.Item1, newValue.Item2);
return(newValue.Item1);
}
/// <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>
/// 安全地获取缓存容器中的值。
/// </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="defaultValue">获取失败后，要返回的缺省值。</param>
/// <returns>获取得到的缓存项的值。</returns>
/// <exception cref="System.ArgumentNullException">container or key</exception>
public static object GetValue(this ICacheContainer container, string key, object defaultValue = null)
{
if (ReferenceEquals(container, null))
{
throw new ArgumentNullException("[ICacheContainerExtensions].[GetValue].container");
}
if (key == null)
{
throw new ArgumentNullException("[ICacheContainerExtensions].[GetValue].key");
}
object value = null;
if (container.TryGetValue(key, out value))
{
return(value);
}
return(defaultValue);
}
/// <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);
}