golang 读取递归文件夹下所有文件

package main

import (
	"fmt"
	"io/ioutil"
)

func main() {
	dirName := "D:\\tmp\\20220314"
	//fmt.Println(dirName)
	res := FileList(dirName, 0)
	for _, file := range res {
		fmt.Println(file)
	}
	
}

func FileList(dirName string, level int) []string {
	/*
		根据层级读取目录下文件  并返回list
	*/
	s := "|--"
	for i := 0; i < level; i++ {
		s = "|  " + s
	}
	var ret []string
	fileInfo, err := ioutil.ReadDir(dirName)
	if err != nil {
		fmt.Println(err)
		return ret
	}
	for _, fi := range fileInfo {
		fileName := dirName + "/" + fi.Name()
		fmt.Printf("%s%s\n", s, fileName)
		if fi.IsDir() {
			tmpRes := FileList(fileName, level+1)
			ret = append(ret, tmpRes...)
		} else {
			ret = append(ret, fileName)
		}
	}
	return ret
}