获取Golang中给定文件路径的目录名称（不是路径）

Question

By using the path/filepath package with the following example, you can get the full directory path from a file path.

package main

import (
    "fmt"
    "path/filepath"
)

func main() {
    // Output: /path/to/dir
    fmt.Println(filepath.Dir("/path//to/dir/file.ext"))
}

But is there a Parent function to get the dir from the path? (which is the name of the directory of the file):

// The `Parent` is what I want,
// and this is a pseudo-code example, this won't actually work.
//
// Output: dir
fmt.Println(filepath.Parent("/path//to/dir/file.ext"))

If it can't be done with the functions, how do I get the parent's name with RegExp?

Answer 1

You can use filepath.Base to get the last element of the directory. For example:

package main

import (
    "fmt"
    "path/filepath"
)

func main() {
    paths := []string{
        "/home/arnie/amelia.jpg",
        "/mnt/photos/",
        "rabbit.jpg",
        "/usr/local//go",
    }
    for _, p := range paths {
        dir := filepath.Dir(p)
        parent := filepath.Base(dir)
        fmt.Printf("input: %q
\tdir: %q
\tparent: %q
", p, dir, parent)
    }
}

Returns:

input: "/home/arnie/amelia.jpg"
    dir: "/home/arnie"
    parent: "arnie"
input: "/mnt/photos/"
    dir: "/mnt/photos"
    parent: "photos"
input: "rabbit.jpg"
    dir: "."
    parent: "."
input: "/usr/local//go"
    dir: "/usr/local"
    parent: "local"

(example adapted from the filepath examples)