学步园

利用 for-in 循环来遍历字符串中的每一个字符：

for character in "hello word!" {
    println(character)
}

使用countElements() 函数计算字符串长度

println(countElements("hello word!"))

使用hasPrefix 和 hasSuffix 方法来判断字符串的前缀和后缀是否相等

let romeoAndJuliet = [
    "Act 1 Scene 1: Verona, A public place",
    "Act 1 Scene 2: Capulet's mansion",
    "Act 1 Scene 3: A room in Capulet's mansion",
    "Act 1 Scene 4: A street outside Capulet's mansion",
    "Act 1 Scene 5: The Great Hall in Capulet's mansion",
    "Act 2 Scene 1: Outside Capulet's mansion",
    "Act 2 Scene 2: Capulet's orchard",
    "Act 2 Scene 3: Outside Friar Lawrence's cell",
    "Act 2 Scene 4: A street in Verona",
    "Act 2 Scene 5: Capulet's mansion",
    "Act 2 Scene 6: Friar Lawrence's cell"
]

var act = 0
var mansion = 0
for scene in romeoAndJuliet {
    if scene.hasPrefix("Act 1 ") {
        ++act
    }
    
    if scene.hasSuffix("Capulet's mansion"){
        ++mansion;
    }
}

println("act: \(act)  sapuletMansion: \(mansion)");

使用 uppercaseString 和 lowercaseString 属性访问一个字符串的大、小写版本

let normal = "Could you help me, please?"

println(normal.uppercaseString)
println(normal.lowercaseString)
//
//COULD YOU HELP ME, PLEASE?
//could you help me, please?