操作符
swift中运算符基本基础于c,下面我就给大家白话白话那些被优化过的运算符们
//加号减号的妙用
var a=
var b= -a//此时b=-1
var c = +b//此时 c=-1
var d= - c//此时 d=1
操作符
//操作符(数字...数字1)表示从数字到数字1之间的数其中包括数字和数字1
for var i in ...{
printlin("数字:\(i)进化后:\(i*6)")
}
/*输出
数字:1进化后:6
数字:2进化后:12
数字:3进化后:18
数字:4进化后:24
数字:5进化后:30
*/
字符串
swift里面用到的字符串默认都是utf-16字符编码,无论是标识符还是自定义字符串
字符串拼接用加号(+)
字符串遍历用for...in
//字符串拼接
var a="Hello"
var b="world"
var c=" "
println(a+c+b)//输出Hello World
println(a+b)//输出HelloWorld
//字符串遍历
for i in a{
print("\(i) ")//输出:H e l l o
}
//获取字符串长度countElements
print(countElements(a))//5
//字符串赋值
“let wiseWords = "\"Imagination is more important than knowledge\" - Einstein"
// "Imagination is more important than knowledge" - Einstein
let dollarSign = "\x24" // $, Unicode scalar U+0024
let blackHeart = "\u2665" // ♥, Unicode scalar U+2665
let sparklingHeart = "\U0001F496" //