IReadOnlyDictionary<TKey,TValue>.ContainsKey(TKey) Method

Reference

Definition

Namespace:: System.Collections.Generic

Assembly:: System.Runtime.dll

Assembly:: mscorlib.dll

Assembly:: netstandard.dll

Important

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Determines whether the read-only dictionary contains an element that has the specified key.

public:
 bool ContainsKey(TKey key);

public bool ContainsKey (TKey key);

abstract member ContainsKey : 'Key -> bool

Public Function ContainsKey (key As TKey) As Boolean

Parameters

key: TKey

The key to locate.

Returns

Boolean

true if the read-only dictionary contains an element that has the specified key; otherwise, false.

Exceptions

ArgumentNullException

key is null.

Remarks

Implementations can vary in how they determine the equality of objects; for example, the class that implements IReadOnlyDictionary<TKey,TValue> might use the Comparer<T>.Default property, or it might implement the IComparer<T> method.

Implementations can vary in whether they allow key to be null.

Applies to

Jaa