Swift-3-字符串和字符
// Playground - noun: a place where people can play import UIKit var someString = "some string literal value" someString += "another" // 初始化空字符串 2种方式,得出的结果一致 var emptyString = "" var anotherEmptyString = String() if emptyString.isEmpty { println("emptyString is empty") } // 可变字符串 var varibleString = "hosrse" varibleString += "and carriage" let constantString = "hignlander" //constantString += "anything" // 字符串常量不能修改,出错 // swift中字符串是值类型 value type // 连接字符串 var string1 = "hello" var string2 = " there" var welcome = string1 + string2 // 向字符串后添加字符 let exclamationMark : Character = "!" welcome.append(exclamationMark) // 字符串插值 \() let multiplier = 3 let message = "\(multiplier) times 2.5 is \(Double(multiplier) * 2.5)"