@H_502_0@Var 定义变量

@H_502_0@Let 定义常量

@H_502_0@printf() 打印

@H_502_0@var num = 1 //int变量

@H_502_0@var num = 10.0 //double 变量

@H_502_0@

@H_502_0@字符串

@H_502_0@NSString ---> String "String" 直接双引号 可以像脚本语言一样直接对字符串想加减,可以带入变量

@H_502_0@let c = "cap"

let d = "I have \(c) apples"// \(c)将常量c填充入字符串，类似format、

@H_502_0@数组

@H_502_0@NSArray --->声明空数组的话使用[] 或者let emptyArray = [String]()

@H_502_0@let arr = ["a","b","c"]

@H_502_0@NSMutableArray--->

@H_502_0@var arr = ["a","c"]

@H_502_0@arr[0] = "apple" //替换元素

@H_502_0@

@H_502_0@字典

@H_502_0@NSDictionary--->声明空字典的话使用[:] 或者let emptyDictionary = [String: Float]()

@H_502_0@let dic = ["keyA":"A","keyB":"b","keyC":"c"]

@H_502_0@NSMutableDictionary--->

@H_502_0@var dic = ["keyA":"A","keyC":"c"]

@H_502_0@//addobject 添加

@H_502_0@dic["KeyD"]="D" //相当于字典addobject

@H_502_0@

//setobject 设置

dic["D"] = "Dan"

print("dic=",dic)

//removeObjectForKey 移除某个key和对应的键值

dic["D"] = nil

//removeAllobject 移除所有

dic = [:]

print("dic)