Go语言库系列之flag的具体使用

$ flag girl -h
Usage of girl:
 -height int
  身高 (default 140)

import "flag"

var height int

flag.IntVar(&height, "height", 140, "身高")

flag.Parse()

fmt.Println("恭喜你获得了身高", height, "的女朋友")

package main

import (
 "flag"
 "fmt"
)

var height int

func main() {
 flag.IntVar(&height, "height", 140, "身高")
 flag.Parse()
 fmt.Println("恭喜你获得了身高", height, "的女朋友")
}

$ girl -height 170
$ girl --height 170
$ girl --height=170
$ girl -height=170

1, 0, t, f, T, F, true, false, TRUE, FALSE, True, False

type height int

func (h *height) String() string {
 return fmt.Sprint(*h)
}

func (h *height) Set(value string) error {
 valueInt, _ := strconv.Atoi(value)
 *h = height(valueInt - 5)
 return nil
}

var heightFlag height

func main() {
 flag.Var(&heightFlag, "height", "身高")
 flag.Parse()
 fmt.Println(heightFlag)
}