go语言中的解析命令行参数

package main

import(
	"fmt"
	"flag"
)

func main(){
	var user string
	var pwd string 
	var host string
	var port int 
	// &user为-u后面的参数值
	flag.StringVar(&user,"u","","用户名默认为空")
	flag.StringVar(&pwd,"pwd","","密码默认为空")
	flag.StringVar(&host,"localhost","","主机名默认为localhost")
	flag.IntVar(&port,"p",3306,"端口默认为3306")
	// 重要操作，必须调用这个方法
	flag.Parse()
	fmt.Printf("user=%v pwd=%v host=%v port=%v",user,pwd,host,port)

}