Swift characters in strings

What are the string and Character Types of Swift ?? Provides a fast and Unicode-compatible way to process code.

String constant

let strTest = "I‘m Swift"

String null value judgment

let  emptyString = ""if emptyString.isEmpty {2. println("Nothing to see here")3. }

String variability. The variability of the string is determined by VAR or let. VaR indicates variable strings, and let indicates constant strings.

var strMsg = "test message"strMsg = "reset message"let strConst = "msg const"

String concatenation string supports the plus (+) and minus (+ =) operations.

var strMsg = "msg "let strConst = "const "strMsg = strMsg + strConststrMsg += "endl"println("\(strMsg)")

String is a collection of single Unicode characters character

For char in "TST ** Han" {println ("\ (char) \ n ")}

Number of string characters. Use the countelements Function

VaR strtest = "C plug is te" println ("\ (countelements (strtest ))")

String comparison provides three methods to compare string values: equal strings, equal prefixes, and equal suffixes. String =

Hasprefix/hassuffix method to check whether the string has a specific prefix/suffix

VaR strtest = "C plug is te" Var strsecond = "C plug is te" If strtest = strsecond {println ("same");} If strtest. hassuffix ("te") {println ("has SUF ");}

String case-sensitive version

Returned by uppercasestring and lowercasestring of the string

 

Let normal = "Hello, Ketty! Hello "Var shouty = normal. uppercasestringvar whispered = normal. lowercasestringprintln (" \ (shouty) \ n \ (Whispered) ") // output hello, Ketty! Hello, Ketty! Hi!

 

Character Type Declaration

Let chtest: character = "" // here is double quotation marks.