Golang File Paths | Portable Path Operations

$ go run file-paths.go
p: dir1/dir2/filename
dir1/filename
dir1/filename
Dir(p): dir1/dir2
Base(p): filename
false
true
.json
config
t/file
../c/t/file 

// The `filepath` package provides functions to parse
// and construct *file paths* in a way that is portable
// between operating systems; `dir/file` on Linux vs.
// `dir\file` on Windows, for example.
package main import ( "fmt" "path/filepath" "strings"
) func main() { // `Join` should be used to construct paths in a // portable way. It takes any number of arguments // and constructs a hierarchical path from them. p := filepath.Join("dir1", "dir2", "filename") fmt.Println("p:", p) // You should always use `Join` instead of // concatenating `/`s or `\`s manually. In addition // to providing portability, `Join` will also // normalize paths by removing superfluous separators // and directory changes. fmt.Println(filepath.Join("dir1//", "filename")) fmt.Println(filepath.Join("dir1/../dir1", "filename")) // `Dir` and `Base` can be used to split a path to the // directory and the file. Alternatively, `Split` will // return both in the same call. fmt.Println("Dir(p):", filepath.Dir(p)) fmt.Println("Base(p):", filepath.Base(p)) // We can check whether a path is absolute. fmt.Println(filepath.IsAbs("dir/file")) fmt.Println(filepath.IsAbs("/dir/file")) filename := "config.json" // Some file names have extensions following a dot. We // can split the extension out of such names with `Ext`. ext := filepath.Ext(filename) fmt.Println(ext) // To find the file's name with the extension removed, // use `strings.TrimSuffix`. fmt.Println(strings.TrimSuffix(filename, ext)) // `Rel` finds a relative path between a *base* and a // *target*. It returns an error if the target cannot // be made relative to base. rel, err := filepath.Rel("a/b", "a/b/t/file") if err != nil { panic(err) } fmt.Println(rel) rel, err = filepath.Rel("a/b", "a/c/t/file") if err != nil { panic(err) } fmt.Println(rel)
}