使用go的net/http實現讀取web頁面

這是一個建立於 的文章，其中的資訊可能已經有所發展或是發生改變。

package main

import (

 "fmt"

 "io/ioutil" //[1]

 "net/http" //[2]

 "os" //[3]

 "path/filepath" // [4]

)

func main() {

 if len(os.Args) != 2 {

 fmt.Printf("useage:%s http://url", filepath.Base(os.Args[0]))

 os.Exit(1)

 }

 resp, err := http.Get(os.Args[1])

 if err != nil {

 fmt.Println(err) //go語言會內含詳細的錯誤描述，可以嘗試不同的參數來測試

 os.Exit(2)

 }

 defer resp.Body.Close() //The client must close the response body when finished with it: 

 body, err2 := ioutil.ReadAll(resp.Body) //此處使用了包【1】

 if err2 != nil {

 fmt.Println(err2)

 os.Exit(3)

 }

 fmt.Printf("%s", body)

}

##產生程式測試 getwebpage.exe
useage:getwebpage.exe http://url getwebpage.exe http://ww
Get http://ww: dial tcp: GetAddrInfoW: No such host is known. getwebpage.exe htt
Get htt: unsupported protocol scheme ""

相關說明  在DOS裡執行命令 “godoc -http=:8000”後可以查到相關包 http://127.0.0.1:8000/pkg/net/http/ http://127.0.0.1:8000/pkg/io/ioutil/#ReadAll Package http provides HTTP client and server implementations. Get, Head, Post, and PostForm make HTTP (or HTTPS) requests: resp, err := http.Get("http://example.com/") ... resp, err := http.Post("http://example.com/upload", "image/jpeg", &buf) ... resp, err := http.PostForm("http://example.com/form",   url.Values{"key": {"Value"}, "id": {"123"}})
//func ReadAll(r io.Reader) ([]byte, error) ReadAll reads from r until an error or EOF and returns the data it read. A successful call returns err == nil, not err == EOF. Because ReadAll is defined to read from src until EOF, it does not treat an EOF from Read as an error to be reported.