**注冊 Request Handler** ~~~go func (w http.ResponseWriter, r *http.Request) ~~~ 這個函數接收兩個參數： http.ResponseWriter：text/html響應 http.Request：包含關于這個HTTP請求的所有信息，包括像URL或header simple demo ~~~go http.HandleFunc("/", func (w http.ResponseWriter, r *http.Request) { fmt.Fprintf(w, "Hello, you've requested: %s\n", r.URL.Path) }) ~~~ 一個request handler 無法接受外部HTTP的請求，需要一個監聽某個端口的http server來處理request，將其傳給對應的request handler。 ~~~go http.ListenAndServe(":80", nil) ~~~ <details> <summary> Demo </summary> ``` package main import ( "fmt" "net/http" ) func main() { http.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) { fmt.Fprintf(w, "Hello, you've requested: %s\n", r.URL.Path) }) http.ListenAndServe(":80", nil) } ``` </details> ***** **http.FileServer** ``` fs := http.FileServer(http.Dir("static/")) http.Handle("/static/", http.StripPrefix("/static/", fs)) ```