如何使用Go编程语言对文件名进行排序？

In my Go project, I need to sort the .json files and to display their name on the terminal when I'm running this command on the terminal go run main.go.

I coded a program which displays all the files in the folder, but I need to sort the .json file.

My code is the following :

package main

import (
    "fmt"
    "log"
    "os"
    "bytes"
    "io"
)

func main() {

    if os.Args[1] == "display-json-name" {
        //reads the directory name and returns a list of directory entries
        dirname := "." 

        f, err := os.Open(dirname)
        if err != nil {
            log.Fatal(err)
        }
        files, err := f.Readdir(-1)
        f.Close()
        if err != nil {
            log.Fatal(err)
        }

        for _, file := range files {
            fmt.Println(file.Name())
        }
    }

How can we sort just the different .json files?

And the hierarchy of my project is :

Based on comments, it appears that the question is "How to print files where the file has a .json extension". Here's the code:

if os.Args[1] == "display-json-name" {
    //reads the directory name and returns a list of directory entries
    dirname := "."

    f, err := os.Open(dirname)
    if err != nil {
        log.Fatal(err)
    }
    files, err := f.Readdir(-1)
    f.Close()
    if err != nil {
        log.Fatal(err)
    }

    for _, file := range files {
        if filepath.Ext(file.Name()) == ".json" {
            fmt.Println(file.Name())
        }
    }
}

https://golang.org/pkg/io/ioutil/#ReadDir

package main

import (
    "fmt"
    "io/ioutil"
    "log"
)

func main() {
    files, err := ioutil.ReadDir(".")
    if err != nil {
        log.Fatal(err)
    }

    for _, file := range files {
        fmt.Println(file.Name())
    }
}