// 定义空的字符串
var str1 = ""
var str2 = String()
str1.isEmpty // 判断字符串是否为空
// 输出字符串中所有的字符
var str3 = "As god name"
for c in str3{
println(c)
}
Int.max // Int类型的最大值
Int.min // Int类型的最小值
var arr1 = ["c","oc","ios","swift"]
var count = 0
for name in arr1{
if name.hasPrefix("i"){ // hasPrefix 前缀
count++
count
}
}
count = 0
for name in arr1{
if name.hasSuffix("s"){ // hasSuffix 后缀
count++
count
}
}
var string1:String = " Hello,swift!! "
var string2 = "As god name"
// uppercaseString lowercaseString
string2.uppercaseString
string2.lowercaseString
// trim 去掉字符串前后的空白
string1.stringByTrimmingCharactersInSet(NSCharacterSet.whitespaceAndNewlineCharacterSet())
string1.stringByTrimmingCharactersInSet(NSCharacterSet(charactersInString: " H"))
// split
string2.componentsSeparatedByString(" ")
var string3 = "welcome to play swift! Step-by-Step learn from now"
string3.componentsSeparatedByCharactersInSet(NSCharacterSet(charactersInString: "-"))
// join
var string4 = "-"
string4.join(["one","two","three"])
var string5 = "--"
var arr = ["ios","swift","oc"]
string5.join(arr)
var str = "Welcome to play Swift! Step by Step learn Swift language from now"
// range
str.rangeOfString("Step")
str.rangeOfString("Step",options:NSStringCompareOptions.BackwardsSearch)
str.rangeOfString("welcome",options:NSStringCompareOptions.CaseInsensitiveSearch)
str.startIndex
str.endIndex
countElements(str)
var str = "Hello,playground"
let strRange = Range<String.Index>(start:str.startIndex,end:str.endIndex)