Go Flag包-命令行参数解析

Flag包用法

package main

import (
    "flag"
    "fmt"
)

func main() {

    var num int
    var mode string
    var encrypt bool

    // usage
    // cmd -flag
    // cmd --flag
    // cmd -flag=
    // cmd --flag=

    // 第一步，定义Flag参数
    flag.IntVar(&num, "num", 16, "-num the password length")
    //var num = flag.Int("num", 16, "-num the password length")


    flag.StringVar(&mode, "mode", "mix", "-mode the password generate mode")
    // var mode = flag.String("mode", "mix", "-mode the password generate mode")

    flag.BoolVar(&encrypt, "encrypt",true, "-encrypt the password use RSA")
    //var encrypt = flag.Bool("encrypt",true, "-encrypt the password use RSA")


    // 第二步，调用flag.Parse()解析命令行参数到定义的Flag
    flag.Parse()

    // 调用Parse解析后，就可以直接使用绑定的变量了
    fmt.Printf("num:%d mode:%s encrypt:%v\n", num, mode, encrypt)

}