Class SingleCreationValueCache<TKey, TValue>

A dictionary-like type intended for thread-safe value caches whose values are created only once ever.

Inheritance
System.Object
SingleCreationValueCache<TKey, TValue>
Inherited Members
System.Object.ToString()
System.Object.Equals(System.Object)
System.Object.Equals(System.Object, System.Object)
System.Object.ReferenceEquals(System.Object, System.Object)
System.Object.GetHashCode()
System.Object.GetType()
System.Object.MemberwiseClone()
Namespace: IPA.Utilities.Async
Assembly: IPA.Loader.dll
Syntax
public class SingleCreationValueCache<TKey, TValue>
Type Parameters
Name Description
TKey

the key type of the cache
TValue

the value type of the cache
Remarks

This object basically wraps a System.Collections.Concurrent.ConcurrentDictionary`2 with some special handling to ensure that values are only created once ever, without having multiple parallel constructions.

Constructors

| Improve this Doc View Source

SingleCreationValueCache()

Initializes a new instance of the SingleCreationValueCache<TKey, TValue> class that is empty, has the default concurrency level, has the default initial capacity, and uses the default comparer for the key type.

Declaration
public SingleCreationValueCache()
| Improve this Doc View Source

SingleCreationValueCache(IEnumerable<KeyValuePair<TKey, TValue>>)

Initializes a new instance of the SingleCreationValueCache<TKey, TValue> class that contains elements copied from the specified System.Collections.Generic.IEnumerable<T>, has the default concurrency level, has the default initial capacity, and uses the default comparer for the key type.

Declaration
public SingleCreationValueCache(IEnumerable<KeyValuePair<TKey, TValue>> collection)
Parameters
Type Name Description
System.Collections.Generic.IEnumerable<System.Collections.Generic.KeyValuePair<TKey, TValue>> collection

the System.Collections.Generic.IEnumerable<T> whose element are to be used for the new cache
Exceptions
Type Condition
System.ArgumentNullException

when any arguments are null
System.ArgumentException

collection contains duplicate keys
| Improve this Doc View Source

SingleCreationValueCache(IEnumerable<KeyValuePair<TKey, TValue>>, IEqualityComparer<TKey>)

Initializes a new instance of the SingleCreationValueCache<TKey, TValue> class that contains elements copied from the specified System.Collections.Generic.IEnumerable<T> has the default concurrency level, has the default initial capacity, and uses the specified System.Collections.Generic.IEqualityComparer<T>.

Declaration
public SingleCreationValueCache(IEnumerable<KeyValuePair<TKey, TValue>> collection, IEqualityComparer<TKey> comparer)
Parameters
Type Name Description
System.Collections.Generic.IEnumerable<System.Collections.Generic.KeyValuePair<TKey, TValue>> collection

the System.Collections.Generic.IEnumerable<T> whose elements are to be used for the new cache
System.Collections.Generic.IEqualityComparer<TKey> comparer

the equality comparer to use when comparing keys
Exceptions
Type Condition
System.ArgumentNullException

collection or comparer is null
| Improve this Doc View Source

SingleCreationValueCache(IEqualityComparer<TKey>)

Initializes a new instance of the SingleCreationValueCache<TKey, TValue> class that is empty, has the default concurrency level and capacity, and uses the specified System.Collections.Generic.IEqualityComparer<T>.

Declaration
public SingleCreationValueCache(IEqualityComparer<TKey> comparer)
Parameters
Type Name Description
System.Collections.Generic.IEqualityComparer<TKey> comparer

the equality comparer to use when comparing keys
Exceptions
Type Condition
System.ArgumentNullException

comparer is null

Properties

| Improve this Doc View Source

Count

Gets the number of elements that this cache contains.

Declaration
public int Count { get; }
Property Value
Type Description
System.Int32
| Improve this Doc View Source

IsEmpty

Gets a value that indicates whether this cache is empty.

Declaration
public bool IsEmpty { get; }
Property Value
Type Description
System.Boolean

Methods

| Improve this Doc View Source

Clear()

Clears the cache.

Declaration
public void Clear()
| Improve this Doc View Source

ContainsKey(TKey)

Gets a value indicating whether or not this cache contains key.

Declaration
public bool ContainsKey(TKey key)
Parameters
Type Name Description
TKey key

the key to search for
Returns
Type Description
System.Boolean

true if the cache contains the key, false otherwise
| Improve this Doc View Source

GetOrAdd(TKey, Func<TKey, TValue>)

Gets the value associated with the specified key from the cache. If it does not exist, and no creators are currently running for this key, then the creator is called to create the value and the value is added to the cache. If there is a creator currently running for the key, then this waits for the creator to finish and retrieves the value.

Declaration
public TValue GetOrAdd(TKey key, Func<TKey, TValue> creator)
Parameters
Type Name Description
TKey key

the key to search for
System.Func<TKey, TValue> creator

the delegate to use to create the value if it does not exist
Returns
Type Description
TValue

the value that was found, or the result of creator
| Improve this Doc View Source

ToArray()

Copies the key-value pairs stored by the cache to a new array, filtering all elements that are currently being created.

Declaration
public KeyValuePair<TKey, TValue>[] ToArray()
Returns
Type Description
System.Collections.Generic.KeyValuePair<TKey, TValue>[]

an array containing a snapshot of the key-value pairs contained in this cache
| Improve this Doc View Source

TryGetValue(TKey, out TValue)

Attempts to get the value associated with the specified key from the cache.

Declaration
public bool TryGetValue(TKey key, out TValue value)
Parameters
Type Name Description
TKey key

the key to search for
TValue value

the value retrieved, if any
Returns
Type Description
System.Boolean

true if the value was found, false otherwise

Extension Methods