Instance Property

keys

A collection containing just the keys of the dictionary.

Declaration

var keys: Dictionary<Key, Value>.Keys { get }

Discussion

When iterated over, keys appear in this collection in the same order as they occur in the dictionary’s key-value pairs. Each key in the keys collection has a unique value.

let countryCodes = ["BR": "Brazil", "GH": "Ghana", "JP": "Japan"]
print(countryCodes)
// Prints "["BR": "Brazil", "JP": "Japan", "GH": "Ghana"]"

for k in countryCodes.keys {
    print(k)
}
// Prints "BR"
// Prints "JP"
// Prints "GH"

See Also

Accessing Keys and Values

subscript(Key) -> Value?

Accesses the value associated with the given key for reading and writing.

subscript(Key, default: () -> Value) -> Value

Accesses the value with the given key. If the dictionary doesn’t contain the given key, accesses the provided default value as if the key and default value existed in the dictionary.

func index(forKey: Key) -> Dictionary<Key, Value>.Index?

Returns the index for the given key.

subscript(Dictionary<Key, Value>.Index) -> Dictionary<Key, Value>.Element

Accesses the key-value pair at the specified position.

var values: Dictionary<Key, Value>.Values

A collection containing just the values of the dictionary.

var first: (key: Key, value: Value)?

The first element of the collection.

func randomElement() -> (key: Key, value: Value)?

Returns a random element of the collection.

func randomElement<T>(using: inout T) -> (key: Key, value: Value)?

Returns a random element of the collection, using the given generator as a source for randomness.