Go言語for loop文の基本的な使い方と例

for {} // wireless loop

for conditional statement {}

for initial statement; conditional statement; post-iterative statement {}

for key,value:=range Expression/variable {}

func readFile() {
	//need to import bufio, io, os packages
	f, err := os.Open("abc.txt")
	if err ! = nil {
		fmt.Println("open error")
		return
	}
	defer f.Close()

	br := bufio.NewReader(f)
	for {
		s, _, c := br.ReadLine()
		if c == io.EOF {
			break
		}
		fmt.Println(string(s))
	}
}

for i := 1; i < 10; i++ {
	for j := 1; j <= i; j++ {
		fmt.Printf("%dx%d=%d ", j, i, i*j)
	}
	fmt.Println("")
}

// Only English letters can be printed, not Chinese friendly
var str = "Hello world!"
for i := 0; i < len(str); i++ {
	fmt.Printf("str[%d]=%c\n", i, str[i])
}

//need to convert with the help of rune, which is equivalent to char in other languages
var str = "Hello Beijing"
str2 := []rune(str)
for i := 0; i < len(str2); i++ {
	fmt.Printf("str[%d]=%c\n", i, str2[i])
}