Go switch

1 개요

Go switch

• 다른 언어와 달리 break를 사용하지 않는다.

해당 case 코드블럭이 끝나면 break되는 것과 같다.

2 값 case

package main
import "fmt"
func main() {
	weekday := "Saturday"
	switch weekday {
	case "Saturday":
		fmt.Println("Weekend - Saturday")
	case "Sunday":
		fmt.Println("Weekend - Sunday")
	default:
		fmt.Println("Weekday")
	}
}

package main
import (
	"fmt"
	"runtime"
)
func main() {
	fmt.Print("Go runs on ")
	switch os := runtime.GOOS; os {
	case "darwin":
		fmt.Println("OS X.")
	case "linux":
		fmt.Println("Linux.")
	default:
		// freebsd, openbsd,
		// plan9, windows...
		fmt.Printf("%s.\n", os)
	}
}

3 여러 값 case

package main

import "fmt"

func main() {
	for i := 1; i <= 4; i++ {
		printDigitParity(i)
	}
}

func printDigitParity(num int) {
	switch num {
	case 1, 3, 5, 7, 9:
		fmt.Println(num, "odd")
	case 0, 2, 4, 6, 8:
		fmt.Println(num, "even")
	}
}

4 조건 case

package main
import "fmt"
func main() {
	score := 90
	switch {
	case score > 80:
		fmt.Println("High Score")
	case score < 20:
		fmt.Println("Low Score")
	default:
		fmt.Println("Middle Score")
	}
}

package main
import "fmt"
func main() {
	x := 'A'
	switch {
	case '0' <= x && x <= '9':
		fmt.Println("숫자")
	case 'a' <= x && x <= 'z':
		fmt.Println("소문자")
	case 'A' <= x && x <= 'Z':
		fmt.Println("대문자")
	default:
		fmt.Println("특수문자")
	}
}

5 같이 보기

• Go for
• Go goto
• Go 열거형
• Go If와 else
• Go fallthrough
• switch

6 참고

• https://tour.golang.org/flowcontrol/9
• https://mingrammer.com/gobyexample/switch/
• https://www.programiz.com/golang/switch