Decode utf16 (little or big endian) to string

utf16.go

package main

import (
	"bytes"
	"encoding/binary"
	"fmt"
	"unicode/utf16"
)

func DecodeUtf16(b []byte, order binary.ByteOrder) (string, error) {
	ints := make([]uint16, len(b)/2)
	if err := binary.Read(bytes.NewReader(b), order, &ints); err != nil {
		return "", err
	}
	return string(utf16.Decode(ints)), nil
}

func main() {
	b := []byte{
		0xff, // BOM
		0xfe, // BOM
		0x3D, // Pile
		0xD8, // of
		0xA9, // Poo
		0xDC, // ---
		'T',
		0x00,
		'E',
		0x00,
		'S',
		0x00,
		'T',
		0x00,
		0x6C,
		0x34,
		'\n',
		0x00,
	}
	bom := [2]byte{b[0], b[1]}
	var s string
	var err error
	switch bom {
	case [2]byte{0xff, 0xfe}:
		s, err = DecodeUtf16(b[2:], binary.LittleEndian)
	case [2]byte{0xfe, 0xff}:
		s, err = DecodeUtf16(b[2:], binary.BigEndian)
	default: // just try little endian
		s, err = DecodeUtf16(b, binary.LittleEndian)
	}
	if err != nil {
		fmt.Println(err)
	} else {
		fmt.Println(s)
	}
}