Returns a new string made from the receiver by replacing all percent encoded sequences with the matching UTF-8 characters.
- iOS 7.0+
- macOS 10.9+
- tvOS 9.0+
- watchOS 2.0+
A new string with the percent-encoded sequences removed, or
nil if the receiver contains an invalid percent-encoding sequence.
func addingPercentEscapes(using: UInt)
Returns a representation of the receiver using a given encoding to determine the percent escapes necessary to convert the receiver into a legal URL string.