1. go build -o cmd a.go

2. ./cmd -h

golang 中flag包的使用_3g

 

3. ./cmd -name=golanm m123g -age 4 -vip=true -pop 99 简洁 高并发 等等 asdfasfdaf adfa safa adfa fafda adfsafsaf 111111111111111

golang 中flag包的使用_3g_02

 

 

 



package main
import "flag"
import "fmt"
import "strconv"
type percentage float32
func (p *percentage) Set(s string) error {
  v, err := strconv.ParseFloat(s, 32)
  *p = percentage(v)
  return err
}
func (p *percentage) String() string { return fmt.Sprintf("%f", *p) }
func main() {
  namePtr := flag.String("name", "lyh", "user's name")
  agePtr := flag.Int("age", 22, "user's age")
  vipPtr := flag.Bool("vip", true, "is a vip user")
  var email string
  flag.StringVar(&email, "email", "lyhopq@gmail.com", "user's email")
  var pop percentage
  flag.Var(&pop, "pop", "popularity")
  flag.Parse()
  others := flag.Args()
  fmt.Println("name:", *namePtr)
  fmt.Println("age:", *agePtr)
  fmt.Println("vip:", *vipPtr)
  fmt.Println("pop:", pop)
  fmt.Println("email:", email)
  fmt.Println("other:", others)
}