关于Swift 动态生成按钮
//
//
FirstViewController.swift
//
esb
//
//
Created by jiangzhihao on 2018/11/12.
//
Copyright © 2018年 jiangzhihao. All rights reserved.
//
import UIKit
class FirstViewController: UIViewController {
override func viewDid
关于Swift 泛型
// 泛型
// 定义一个交换两个变量的函数
func swap<T>(_ a: inout T, _ b: inout T) {
let temp = a
a = b
b = temp
}
var numb1 = 77
var numb2 = 33
print(“交换前数据: \(numb1) 和 \(numb2)”)
swap(&numb1, &numb2)
print(“交换后数据: \(numb1) 和 \(numb
关于Swift 闭包 Closures
// 闭包
let act = {(val1: String, val2: String) -> String in
return val1.appending(val2)
}
let result = act(“https://”, “chanpinxue.cn”)
print(result)
关于Swift 枚举 enum
// 枚举
enum Action {
case GetUser
case DeleteUser
case UpdateUser
}
var action = Action.GetUser
action = .UpdateUser
switch action
{
case .GetUser:
print(“获取”)
case .DeleteUser:
print(“删除”)
case .UpdateUser:
print(“更新”)
关于Swift 结构体 struct
// 结构体
struct WebInfo {
var https = “https://chanpinxue.cn”
var http = “http://chanpinxue.cn”
}
let miWebInfo = WebInfo()
print(“网站地址 \(miWebInfo.https)”)
关于Swift 字典 Dictionary
// 字典
var users = [1:”jiang”, 2:”jzh”, 3:”hao”]
for (key, value) in users
{
print(“\(key):\(value)”)
}
for key in users.keys
{
print(key)
}
for values in users.values
{
print(values)
}
users.updateValue(“haohao”, forKey:3)
关于Swift if for while case
let value = 20
if (value > 20)
{
print(“大于20”)
}
else if (value < 20)
{
print(“小于20”)
}
else
{
print(“等于20”)
}
let switchCondition:String = “jzh”
switch switchCondition
{
case “jzh”:
print(“ok jzh”);
fallt
关于Swift 数字转字符串 字符串转数字
// 数字转字符串
let number1 = 35
let numStr1 = “\(number1)”
print(numStr1)
// 字符串转化为数字
let numStr2 = “35” as NSString
let number2 = numStr2.intValue
print(number2)
关于Swift 定义函数 返回多个值
// 定义函数，返回值类型是String
func getUser(name: String, age:Int) -> (String)
{
return “name:” + name + ” age:” + “\(age)”
}
// 调用getUser函数
let user = getUser(name: “jzh”, age: 35)
print(“user:\(user)”)
// 调用getUser函数
let user = getUser(n
关于Swift 数组
// 定义并初始化一个数组变量
var arr = [“jiang”, “zhi”, “hao”]
arr.append(“chanpinxue.cn”)
// 枚举数组中的每一个元素值
for element in arr
{
print(element)
}
关于Swift let和var的区别
let 用于定义常量，定义完后不能修改。
var 用于定义变量，可以修改。
let usercode = “9001”
var username = “jzh”
username = “jzh000”
print(usercode)
print(username)