Swift基本运算符和简单的逻辑运算符

1、赋值运算符

var a = 3 //Int

2、基本运算符

var x1 = 10var y1 = 3var z1 = 0//运算符两边变量类型必须一样x1 + y1//强制类型转换Double(x1)/Double(y1)

3、单步运算符

var xx = +x1//+与x1之间不能有空格

4、闭区间运算符

1...10 //[1,10]1..<10 //[1,10)

5、简单的for循环

for index in 1...10{    index}//1到10for index in 1..<10{    index}//1到9

6、三步运算符

var battery = 18var batterColor:UIColorif battery<20 {    batterColor = UIColor.red}else {    batterColor = UIColor.green}//batterColor红色//三步运算符写法var batteryColor2 = battery < 20 ?UIColor.red:UIColor.green