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MemoryCache.CreateCacheEntryChangeMonitor Method

Definition

Creates a CacheEntryChangeMonitor object that can trigger events in response to changes to specified cache entries.

public override System.Runtime.Caching.CacheEntryChangeMonitor CreateCacheEntryChangeMonitor (System.Collections.Generic.IEnumerable<string> keys, string regionName = default);
override this.CreateCacheEntryChangeMonitor : seq<string> * string -> System.Runtime.Caching.CacheEntryChangeMonitor
Public Overrides Function CreateCacheEntryChangeMonitor (keys As IEnumerable(Of String), Optional regionName As String = Nothing) As CacheEntryChangeMonitor

Parameters

keys
IEnumerable<String>

An enumeration of unique cache entry keys for the CacheEntryChangeMonitor object.

regionName
String

A named region in the cache to which a cache entry can be added. Do not pass a value for this parameter. This parameter is null by default, because the MemoryCache class does not implement regions.

Returns

A change monitor that monitors entries in the cache.

Exceptions

regionName is not null.

keys is null.

An item in the keys collection is null.

Remarks

The CreateCacheEntryChangeMonitor method creates a CacheEntryChangeMonitor instance. This specialized change monitor is used to monitor the cache entries that are specified in the keys collection and to trigger events when the entries change.

A monitored entry is considered to have changed for any of the following reasons:

  • The key does not exist at the time of the call to the CreateCacheEntryChangeMonitor method. In that case, the resulting CacheEntryChangeMonitor instance is immediately set to a changed state. This means that when code subsequently binds a change-notification callback, the callback is triggered immediately.

  • The associated cache entry was removed from the cache. This can occur if the entry is explicitly removed, if it expires, or if it is evicted to recover memory

Applies to