发布于 2015-06-14 01:49:17 | 325 次阅读 | 评论: 0 | 来源: 网络整理
您可以通过字符串的uppercaseString和lowercaseString属性来访问大写/小写版本的字符串。
let normal = "Could you help me, please?"
let shouty = normal.uppercaseString
// shouty 值为 "COULD YOU HELP ME, PLEASE?"
let whispered = normal.lowercaseString
// whispered 值为 "could you help me, please?"