Golang : How to Set or Add Header http.ResponseWriter?

Problem :

How to set or add header to http.ResponseWriter?

Solution :

The solution is similar to previous tutorial on how to set or add header to HTTP Request. All you need to do is to use the Add() or Set() methods in the http.ResponseWriter.Header() function. (http://golang.org/pkg/net/http/#ResponseWriter)

For example :

 package main

  import (
 "net/http"
 "strings"
  )

  func SayHelloWorld(w http.ResponseWriter, r *http.Request) {
 w.Write([]byte("Hello, World!"))
  }

  func ReplyName(w http.ResponseWriter, r *http.Request) {
 w.Header().Set("Access-Control-Allow-Origin", "*") //<---------- here! 

 URISegments := strings.Split(r.URL.Path, "/")
 w.Write([]byte(URISegments[1]))
  }

  func main() {
 // http.Handler
 mux := http.NewServeMux()
 mux.HandleFunc("/", SayHelloWorld)
 mux.HandleFunc("/replyname", ReplyName)

 http.ListenAndServe(":8080", mux)
  }