// 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 =
let message = "\(multiplier) times 2.5 is \(Double(multiplier) * 2.5)"