# StringProtocol Implementations ## Topics ### Structures [`struct UTF16View`](/documentation/Swift/Substring/UTF16View) [`struct UTF8View`](/documentation/Swift/Substring/UTF8View) [`struct UnicodeScalarView`](/documentation/Swift/Substring/UnicodeScalarView) ### Operators [`static func != (Self, RHS) -> Bool`](/documentation/Swift/Substring/!=(_:_:)-fryj) [`static func == (Self, RHS) -> Bool`](/documentation/Swift/Substring/==(_:_:)) [`static func > (Self, RHS) -> Bool`](/documentation/Swift/Substring/_(_:_:)-6o7pz) [`static func < (Self, RHS) -> Bool`](/documentation/Swift/Substring/_(_:_:)-8d1w2) [`static func <= (Self, RHS) -> Bool`](/documentation/Swift/Substring/_=(_:_:)-5y23r) [`static func >= (Self, RHS) -> Bool`](/documentation/Swift/Substring/_=(_:_:)-nd7a) ### Initializers [`init(cString: UnsafePointer)`](/documentation/Swift/Substring/init(cString:)) Creates a string from the null-terminated, UTF-8 encoded sequence of bytes at the given pointer. [`init(decoding: C, as: Encoding.Type)`](/documentation/Swift/Substring/init(decoding:as:)) Creates a string from the given Unicode code units in the specified encoding. [`init(decodingCString: UnsafePointer, as: Encoding.Type)`](/documentation/Swift/Substring/init(decodingCString:as:)) Creates a string from the null-terminated sequence of bytes at the given pointer. ### Instance Properties [`var unicodeScalars: Substring.UnicodeScalarView`](/documentation/Swift/Substring/unicodeScalars) [`var utf16: Substring.UTF16View`](/documentation/Swift/Substring/utf16) [`var utf8: Substring.UTF8View`](/documentation/Swift/Substring/utf8) ### Instance Methods [`func hasPrefix(Prefix) -> Bool`](/documentation/Swift/Substring/hasPrefix(_:)) Returns a Boolean value indicating whether the string begins with the specified prefix. [`func hasSuffix(Suffix) -> Bool`](/documentation/Swift/Substring/hasSuffix(_:)) Returns a Boolean value indicating whether the string ends with the specified suffix. [`func hash(into: inout Hasher)`](/documentation/Swift/Substring/hash(into:)) Hashes the essential components of this value by feeding them into the given hasher. [`func lowercased() -> String`](/documentation/Swift/Substring/lowercased()) [`func uppercased() -> String`](/documentation/Swift/Substring/uppercased()) [`func withCString((UnsafePointer) throws(E) -> Result) throws(E) -> Result`](/documentation/Swift/Substring/withCString(_:)) Calls the given closure with a pointer to the contents of the string, represented as a null-terminated sequence of UTF-8 code units. [`func withCString(encodedAs: TargetEncoding.Type, (UnsafePointer) throws(E) -> Result) throws(E) -> Result`](/documentation/Swift/Substring/withCString(encodedAs:_:)) Calls the given closure with a pointer to the contents of the string, represented as a null-terminated sequence of code units. --- Copyright © 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)