Swift相关知识,本随笔为 字符串、数组、字典的简单使用。
///***********************************************************************************************************/
/// 2016.12.29
///***********************************************************************************************************/
1、Swift3 ,字符串的简单使用,直接将代码贴过来,更方便查看
// 字符串 string
func stringTest() -> Void {
// 字符串
let str1 = "yiyi"
let str2 = "2222"
var str3 = String()//空string
var str4 = ""// 空string
// 字符(字符为 一 个)
let char1:Character = "d"
// 字符串长度
var strCount = str1.characters.count
strCount = str1.lengthOfBytes(using: String.Encoding.utf8)
print(String(format:"strCount == "),strCount)
// 字符串转换integer
print((str2 as NSString).integerValue)
// 字符串拼接
str3 = str1 + str2
// str3 = "\(str1)\(str2)"
// str3 = globalStr + String(str1)
print(String(format:"str3 == "),str3)
// 字符串与字符拼接
// str4 = str1+String(char1)
str4 = "\(str1)\(char1)"
str4 = str1.appending(String(char1))// 其他类型转换string String() exp:String(strCount)
print(String(format:""),str4)
//字符串与其他类型值的拼接
let int1 = 10
let int2 = 11.1
let str5 = String(format:"%i%.1f",int1,int2)
print(String(format:"str5 == "),str5)
// 字符串枚举 遍历每个字符
let s1 = "hello world!"
if strCount != 0 {
print("判断string长度不为0,不是空")
}
for c in s1.characters {
print(c)
}
// 字符串比较
let ss1 = "hello"
let ss2 = ",banana"
var ss3 = ss1+ss2
if ss1 == ss2 {
print("ss1=ss2")
}
if ss1+ss2 == ss3 {
print("ss1+ss2=ss3")
}
if ss1 > ss2 {// h大于b
print("ss1>ss2")
}
// 判断字符串是否包含字符串
if (ss3 .range(of: ss1) != nil) {
print("字符串包含子串")
}
if ss3.hasPrefix("he") {}
if ss3.hasSuffix("a") {}
// 字符串 大小写
print(ss3.uppercased())// HELLO,BANANA
print(ss3.capitalized)// Hello,Banana
print(ss3.lowercased())// hello,banana
/*
// 这两个用法没 明白
print(ss3.uppercased(with: Locale(identifier: "l")))// HELLO,BANANA
print(ss3.lowercased(with: Locale(identifier: "o")))// hello,banana
*/
// 截取 修剪 字符串
print(ss3.substring(from: ss3.characters.index(of: ",")!))//,banana 截取字符串从“,”开始
print(ss3.substring(to: ss3.characters.index(of: ",")!))//hello 截取字符串到“,”结束
print(ss3.unicodeScalars[ss3.unicodeScalars.startIndex ..< ss3.unicodeScalars.index(of: ",")!]);// hello
print(ss3[ss3.index(ss3.startIndex, offsetBy: 4)])// o 取字符串的某个字符
ss3.remove(at: ss3.characters.index(of: ",")!)// 去除字符串中特殊字符
print(ss3)// hellobanana
}
2、数组的简单使用
// 数组 array
func arrayTest() -> Void {
// 初始化
// var array1:[Any] = []// 空 任意类型
// var array2 = Array<Any>()
// var array3:[String] = []// 空 string 类型
// var array4 = Array<String>()
// let array5 = Array<Any>(repeatElement("", count: 3))
var arr0 = ["what","test","swift","array"]
let arr1 = ["hyArr",1,"hySwift",3] as [Any]
var arr2 = [1,"2","swiftArr2",3,9,5] as [Any]
print(arr2[0], arr2[3], separator: "* ")
// arr0.count 数组count
print(String(format:"arr0 长度 == "),arr0.count)
// 判断数组是否为空
if arr1.isEmpty {
print