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

Definition

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

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

Exceptions

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