从控制台读取输入

bufio

import (	"bufio"	"os")var r *bufio.Reader = bufio.NewReader(os.Stdin)rawLine, _, _ := r.ReadLine()line := string(rawLine)

rawline是[]byte类型

应该使用 ReadString('\n')，读取的字符串包括 '\n' 字符。

下面是循环读取的例子：

var r *bufio.Reader = bufio.NewReader(os.Stdin)for {	fmt.Print("Enter command ->")	rawLine, _, _ := r.ReadLine()	line := string(rawLine)	if line == "q" || line == "e" {		break	}}

使用 NewScanner

scanner := bufio.NewScanner(os.Stdin)	for scanner.Scan() {		fmt.Println(scanner.Text()) // Println will add back the final '\n'	}	if err := scanner.Err(); err != nil {		fmt.Fprintln(os.Stderr, "reading standard input:", err)	}

Scanner的每一次调用都会调入一个新行，并且会自动将其行末的换行符去掉；其结果可以用input.Text()得到。Scan方法在读到了新行的时候会返回true，而在没有新行被读入时，会返回false

一个词一个词读取

scanner := bufio.NewScanner(os.Stdin)	scanner.Split(bufio.ScanWords)	for scanner.Scan() {		fmt.Println(scanner.Text())	}	if err := scanner.Err(); err != nil {		fmt.Fprintln(os.Stderr, "reading input:", err)	}

fmt

var buf string	for {		_, err := fmt.Scanln(&buf)		if err != nil {			fmt.Println(err)			break		}		fmt.Println(buf)		time.Sleep(100 * time.Microsecond)	}

读取到空格的时候就强制返回了。

还可以定义格式：

var (		name string		age  int	)	for {		_, err := fmt.Scanf("%s %d", &name, &age)		if err != nil {			fmt.Println(err)			break		}		fmt.Printf("name is %s, age is %d\n", name, age)		time.Sleep(100 * time.Microsecond)	}

向错误流输出信息

fmt.Fprint(os.Stderr,"Fatal error: %s\n",err.Error())

清屏

package mainimport (	"os"	"os/exec"	"runtime")var clear map[string]func() //create a map for storing clear funcsfunc init() {	clear = make(map[string]func()) //Initialize it	clear["linux"] = func() {		cmd := exec.Command("clear") //Linux example, its tested		cmd.Stdout = os.Stdout		cmd.Run()	}	clear["windows"] = func() {		cmd := exec.Command("cls") //Windows example it is untested, but I think its working		cmd.Stdout = os.Stdout		cmd.Run()	}}func CallClear() {	value, ok := clear[runtime.GOOS] //runtime.GOOS -> linux, windows, darwin etc.	if ok {                          //if we defined a clear func for that platform:		value() //we execute it	} else { //unsupported platform		panic("Your platform is unsupported! I can't clear terminal screen :(")	}}func main() {	CallClear()}

优雅退出程序（监听ctrl+c事件）

package mainimport (	"fmt"	"os"	"os/signal"	"syscall")func main() {	signalChan := make(chan os.Signal, 1)	signal.Notify(signalChan, syscall.SIGINT, syscall.SIGTERM)	// some code	<-signalChan	fmt.Println("exit by program.")	os.Exit(0)}