ConcurrentDictionary<TKey, TValue>.AddOrUpdate Method (TKey, Func<TKey, TValue>, Func<TKey, TValue, TValue>)
Uses the specified functions to add a key/value pair to the ConcurrentDictionary<TKey, TValue> if the key does not already exist, or to update a key/value pair in the ConcurrentDictionary<TKey, TValue> if the key already exists.
Assembly: mscorlib (in mscorlib.dll)
public TValue AddOrUpdate( TKey key, Func<TKey, TValue> addValueFactory, Func<TKey, TValue, TValue> updateValueFactory )
The key to be added or whose value should be updated
The function used to generate a value for an absent key
Return ValueType: TValue
The new value for the key. This will be either be the result of addValueFactory (if the key was absent) or the result of updateValueFactory (if the key was present).
If you callsimultaneously on different threads, addValueFactory may be called multiple times, but its key/value pair might not be added to the dictionary for every call.
Available since 8
Available since 4.0
Portable Class Library
Supported in: portable .NET platforms
Available since 8.1