swift中方法参数与返回值

//: Playground - noun: a place where people can play

import UIKit

//标签：break可以跳出指定循环
group :
    for _ in 1...2 {
        for _ in 1...3 {
            print("俯卧撑一次")
            break
        }
        print("休息一次")
    }


/// 求两数的和
///
/// - parameter num1: 数字1
/// - parameter num2: 数字2
///
/// - returns: 返回两个数的和
func sum(num1: Int, num2: Int) -> Int{
    return num1 + num2;
}
print(sum(num1: 1, num2: 2))


/// 没有返回值函数，写法1
///
/// - parameter starNum: *号数量
func printStar (starNum: Int) -> Void {
    for _ in 1...starNum {
        print("*")
    }
}
printStar(starNum: 3)

/// 没有返回值函数，写法2
///
/// - parameter starNum: *号数量
func prinrStar2 (starNum: Int) -> (){
    for _ in 1...starNum {
        print("**")
    }
}
prinrStar2(starNum: 4)

/// 没有返回值函数，写法3
///
/// - parameter starNum: *号数量
func printStar3 (starNum: Int) {
    for _ in 1...starNum {
        print("***")
    }
}
printStar3(starNum: 5)

/// 返回元组
///
/// - parameter id: 人物id
///
/// - returns: 返回人物的姓名和年龄
func getPoint(stu_id id: Int) -> (name: String, age: Int) {
    if id > 0 {
        return ("jack", 20)
    } else {
        return ("no", 0)
    }
}
var people = getPoint(stu_id: 10)
print("name=\(people.name), age=\(people.age)")

/// 默认参数
///
/// - parameter name: 姓名
/// - parameter age:  年龄
func student (name: String, _ age: Int = 20) {
    print("name=\(name), age=\(age)")
}
student(name: "jack")

/// 变量参数
///
/// - parameter srcStr: 源字符串
/// - parameter addStr: 加字符串
/// - parameter num:    数量
///
/// - returns: 返回字符串
func append ( srcStr: String, addStr: String, num: Int) -> String {
    var srcStr = srcStr
    for _ in 1...num {
        srcStr += addStr
    }
    return srcStr
}
append(srcStr: "jack", addStr: ".", num: 4)