Contents

removeValue(forKey:)

Removes the given key and its associated value from the dictionary.

Declaration

@discardableResult mutating func removeValue(forKey key: Key) -> Value?

Parameters

  • key:

    The key to remove along with its associated value.

Return Value

The value that was removed, or nil if the key was not present in the dictionary.

Discussion

If the key is found in the dictionary, this method returns the key’s associated value. On removal, this method invalidates all indices with respect to the dictionary.

var hues = ["Heliotrope": 296, "Coral": 16, "Aquamarine": 156]
if let value = hues.removeValue(forKey: "Coral") {
    print("The value \(value) was removed.")
}
// Prints "The value 16 was removed."

If the key isn’t found in the dictionary, removeValue(forKey:) returns nil.

if let value = hues.removeValue(forKey: "Cerise") {
    print("The value \(value) was removed.")
} else {
    print("No value found for that key.")
}
// Prints "No value found for that key."

See Also

Removing Keys and Values