小編最近再看無聞的goweb視屏，總結視屏中三種go響應http的方法

1.直接用 http.HandleFunc() 函數

// object project main.go
package main

import (
    "io"
    "log"
    "net/http"
)

func main() {

    http.HandleFunc("/", sayhello)
    // 第一個參數代表訪問的路徑，第二個代表要執行的函數的名字
    
    err := http.ListenAndServe(":8080", nil)
    //設置端口號，第二個暫時沒有，寫為nil，在接下來的方法中介紹
 

    if err != nil {
        log.Fatal(err)
        //如果err不為空，打印err
    }

}

//ResponseWriter為接口，Request為結構體
func sayhello(w http.ResponseWriter, r *http.Request) {
    io.WriteString(w, "hello!this is version 1")
}

2.介紹Handle方法

package main // dealFile project main.go

import (
    "io"
    "log"
    "net/http"
    "os"
)

func main() {
    
 
//首先實現 NewServeMux()方法
    max := http.NewServeMux()

    max.Handle("/", &myHandler{})
    max.HandleFunc("/hello", sayhello)

    //靜態文件的實現
    wd, err := os.Getwd()
    if err != nil {
        log.Fatal(err)
    }

    max.Handle("/static/",
        http.StripPrefix("/static/",
            http.FileServer(http.Dir(wd))))

    
 
//設置監聽的端口號
    err = http.ListenAndServe(":8080", max)
    if err != nil {
        log.Fatal(err)
    }

}

type myHandler struct{}

//實現ServeHTTP方法
func (*myHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
    io.WriteString(w, "URL:"+r.URL.String())
}

func sayhello(w http.ResponseWriter, r *http.Request) {
    io.WriteString(w, "Hello world,this is version 2")
}

3.Server

package main

import (
    "io"
    "log"
    "net/http"
    "time"
)

var mux map[string]func(http.ResponseWriter, *http.Request)

func main() {
    server := http.Server{
        Addr:        ":8080", //端口號
        Handler:     &myHandler{},  //實現的Handler
        ReadTimeout: 5 * time.Second,  //響應等待時間
    }

    mux = make(map[string]func(http.ResponseWriter, *http.Request))
    mux["/hello"] = sayHello
    mux["/bye"] = sayBye

    err := server.ListenAndServe()
    if err != nil {
        log.Fatal(err)
    }
}

type myHandler struct{}

func (*myHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
    //判斷URL是否為空並輸出
    if h, ok := mux[r.URL.String()]; ok {
        h(w, r)
        return
    }
    io.WriteString(w, "URL:"+r.URL.String())
}

func sayHello(w http.ResponseWriter, r *http.Request) {
    io.WriteString(w, "Hello World")
}

func sayBye(w http.ResponseWriter, r *http.Request) {
    io.WriteString(w, "Bye Bye")
}

響應http的三種方法