Swift 中----字符串和字符

//字符串

let someString = "someString"

//初始化空字符串

var empString = ""

var anotherString = String()

//这俩种形式创建的字符串等价均为空

if empString.isEmpty{

print("这是空的")

}

var cari = "Horse"

var  abc =   someString + cari

print("abc === \(abc)")

/*

 for ac in 0 ... count-1{

 print("第\(ac+1)个人叫\(names[ac])")

 

 }

 

 */

let quo = "Hello World"

let luo = "World,"

if quo == luo{//俩个字符串相等

 

}

//有这个头

if quo .hasPrefix("Hell"){

}

//有这个尾

if luo.hasSuffix("ld"){

}

//大小写字符串

let normal = "Cound you help me, please"

let  shouty = normal.uppercased()//将每个字符转成大写

let  whis =  normal.lowercased()//将每个字符转成小写

print("shouty === \(shouty)")