golang http 服务器通过套接字发送 r.URL.Path

Question

我有一个 http 服务器，我想使用套接字将 r.URL.Path 文本发送到客户端

我得到一个错误:undefined: conn in conn.Write这是因为 conn 是在另一个函数中定义的

我尝试过的:

package main

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


ln, _ := net.Listen("tcp", ":8081")
conn, _ := ln.Accept()

func hello(w http.ResponseWriter, r *http.Request) {
    io.WriteString(w, "Hello world!")
    conn.Write([]byte(r.URL.Path + "\n")) //Here I'm attemping to send it
}

func main() {


    http.HandleFunc("/", hello)
    http.ListenAndServe(":8000", nil)
}

Answer 1

您的问题实际上在于您尝试声明变量的方式。
如果您希望您的连接在全局范围内，请使用 var

package main

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


var ln, _ = net.Listen("tcp", ":8081")
var conn, _ = ln.Accept()

func hello(w http.ResponseWriter, r *http.Request) {
    io.WriteString(w, "Hello world!")
    conn.Write([]byte(r.URL.Path + "\n")) //Here I'm attemping to send it
}

func main() {
    http.HandleFunc("/", hello)
    http.ListenAndServe(":8000", nil)
}