Unescape|Decode UTF-8 String in Go

package main

import "encoding/json"

// Unescape UTF-8 string
// e.g. convert "\u0e27\u0e23\u0e0d\u0e32" to "วรญา"
func UnescapeString(str string) (unescapedString string) {
	json.Unmarshal([]byte(`"`+str+`"`), &unescapedString)
	return
}

You need to escape any the " in the JSON:

package main

import (
	"encoding/json"
	"strings"
)

func UnescapeUTF8(inStr string) (outStr string, err error) {
	jsonStr := `"` + strings.ReplaceAll(inStr, `"`, `\"`) + `"`
	err = json.Unmarshal([]byte(jsonStr), &outStr)
	return
}

rubenhorn excelent solutions very thanks! (y)

There's no need to rely on json.Unmarshal, instead you can use strconv.Unquote directly like so (playground):

source := "\u0e27\u0e23\u0e0d\u0e32"
converted, _ := strconv.Unquote(`"` + source + `"`)
fmt.Println(converted)
// prints วรญา