DictionaryExtensionsTryAddTKey, TValue Method

Tries to add a pair of key and value the specified dictionary. The operation is thread safe if dictionary is a ThreadSafeDictionaryTKey, TValue, ConcurrentDictionaryTKey, TValue or LockingDictionaryTKey, TValue instance. For other IDictionaryTKey, TValue implementations the caller should care about thread safety if needed.

Definition

Namespace: KGySoft.CoreLibraries
Assembly: KGySoft.CoreLibraries (in KGySoft.CoreLibraries.dll) Version: 9.0.0

C#

public static bool TryAdd<TKey, TValue>(
	this IDictionary<TKey, TValue> dictionary,
	KeyValuePair<TKey, TValue> item
)

VB

<ExtensionAttribute>
Public Shared Function TryAdd(Of TKey, TValue) ( 
	dictionary As IDictionary(Of TKey, TValue),
	item As KeyValuePair(Of TKey, TValue)
) As Boolean

C++

public:
[ExtensionAttribute]
generic<typename TKey, typename TValue>
static bool TryAdd(
	IDictionary<TKey, TValue>^ dictionary, 
	KeyValuePair<TKey, TValue> item
)

F#

[<ExtensionAttribute>]
static member TryAdd : 
        dictionary : IDictionary<'TKey, 'TValue> * 
        item : KeyValuePair<'TKey, 'TValue> -> bool

Parameters

dictionary IDictionaryTKey, TValue: The target dictionary.
item KeyValuePairTKey, TValue: The KeyValuePairTKey, TValue to add to the dictionary.

Type Parameters

TKey: The type of the keys in the dictionary.
TValue: The type of the values in the dictionary.

Return Value

Boolean
if item was added to the dictionary successfully; if the key already exists or when IsReadOnly returns for dictionary.

Usage Note

In Visual Basic and C#, you can call this method as an instance method on any object of type IDictionaryTKey, TValue. When you use instance method syntax to call this method, omit the first parameter. For more information, see Extension Methods (Visual Basic) or Extension Methods (C# Programming Guide).

Remarks

The CollectionExtensions class in .NET Core 2.0 and above also has a TryAdd method that behaves somewhat differently. To avoid ambiguity with that method this one has a KeyValuePairTKey, TValue parameter.

Unlike the CollectionExtensions.TryAdd method, this one is thread safe when used with ConcurrentDictionaryTKey, TValue, ThreadSafeDictionaryTKey, TValue and LockingDictionaryTKey, TValue instances. Additionally, this one returns if dictionary is read-only instead of throwing an exception.

Exceptions

ArgumentNullException	dictionary is .
ArgumentException	item has a key.