//: Playground - noun: a place where people can play

import Foundation

var str = "Hello, playground"

str.capitalizedString   // 字符串中所有单词首字母大写, 不改变str本身的值

str

str += ", hello, rinpe chan"

str.capitalizedString

str.uppercaseString     // 全大写

str.lowercaseString     // 全小写

// trim

var str2 = "   hi    ?!@"

str2.stringByTrimmingCharactersInSet(NSCharacterSet(charactersInString: " !?@"))     // 切除字符串中的字符

// split

var str3 = "welcome to Shantou"

str3.componentsSeparatedByString(" ")   // 分割

// 分割更复杂的字符串

var str4 = "rinpe, bobo! how-are-u?"

str4.componentsSeparatedByCharactersInSet(NSCharacterSet(charactersInString: " !-?"))

// join

var str5 = "-"

["1", "2", "3"].joinWithSeparator(str5)