Go命令行应用开发指南

import (
    "flag"
    "fmt"
)

func main() {
    name := flag.String("name", "World", "A name to say hello to")
    flag.Parse()
    fmt.Printf("Hello, %s!\n", *name)
}

./app -name Alice
# 输出: Hello, Alice!

import (
    "fmt"
    "os"
)

func main() {
    if len(os.Args) > 1 {
        fmt.Printf("Hello, %s!\n", os.Args[1])
    } else {
        fmt.Println("Hello, World!")
    }
}

./app Alice
# 输出: Hello, Alice!

import (
    "bufio"
    "fmt"
    "os"
)

func main() {
    reader := bufio.NewReader(os.Stdin)
    fmt.Print("Enter your name: ")
    name, _ := reader.ReadString('\n')
    fmt.Printf("Hello, %s", name)
}

import (
    "fmt"
    "github.com/spf13/cobra"
)

var rootCmd = &cobra.Command{
    Use:   "app",
    Short: "A brief description of your application",
    Long: `A longer description that spans multiple lines and likely contains
examples and usage of using your application.`,
    Run: func(cmd *cobra.Command, args []string) {
        fmt.Println("Hello from Cobra!")
    },
}

func main() {
    rootCmd.Execute()
}

import (
    "fmt"
    "github.com/urfave/cli/v2"
    "os"
)

func main() {
    app := &cli.App{
        Name:  "greet",
        Usage: "fight the loneliness!",
        Action: func(c *cli.Context) error {
            name := "World"
            if c.NArg() > 0 {
                name = c.Args().Get(0)
            }
            fmt.Printf("Hello, %s!\n", name)
            return nil
        },
    }

    app.Run(os.Args)
}