gopl-Exercise1.7-9: Fetch_goplijmuhbfcefq-优快云博客

本文主要完成The Golang Programming Language中，1.7-9的练习。

源码fetch.go

// Copyright © 2016 Alan A. A. Donovan & Brian W. Kernighan.
// License: https://creativecommons.org/licenses/by-nc-sa/4.0/

// See page 16.
//!+

// Fetch prints the content found at each specified URL.
package main

import (
    "fmt"
    "io"
    // "io/ioutil"
    "log"
    "net/http"
    "os"
    "strings"
)

func main() {
    for _, url := range os.Args[1:] {
        // Exercise 1.8
        if !strings.HasPrefix(url, "http://") {
            fmt.Printf("%s not has prefix http://", url)
        }
        resp, err := http.Get(url)
        if err != nil {
            fmt.Fprintf(os.Stderr, "fetch: %v\n", err)
            os.Exit(1)
        }
        // Exercise 1.9
        fmt.Printf("%s", resp.Status)
        fmt.Println("...............")

        // Exercise 1.7
        if b, err := io.Copy(os.Stdout, resp.Body); err != nil {
            log.Fatal(err)
        } else {
            fmt.Printf("%s", b)
        }
        resp.Body.Close()
        // b, err := ioutil.ReadAll(resp.Body)
        // resp.Body.Close()
        // if err != nil {
        //  fmt.Fprintf(os.Stderr, "fetch: reading %s: %v\n", url, err)
        //  os.Exit(1)
        // }
        // fmt.Printf("%s", b)
    }
}
//!-

运行结果

$ go build
$ ./fetch.exe http://gopl.io                                                                                                                                              /c/Users/Administrator/go/src/gopl.io/ch1/fetch
200 OK...............
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
          "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
  <meta name="go-import" content="gopl.io git https://github.com/adonovan/gopl.io"></meta>
  <title>The Go Programming Language</title>
  <script>
  (function(i,s,o,g,r,a,m){i['GoogleAnalyticsObject']=r;i[r]=i[r]||function(){
  (i[r].q=i[r].q||[]).push(arguments)},i[r].l=1*new Date();a=s.createElement(o),
  m=s.getElementsByTagName(o)[0];a.async=1;a.src=g;m.parentNode.insertBefore(a,m)
  })(window,document,'script','//www.google-analytics.com/analytics.js','ga');

  ga('create', 'UA-68781809-1', 'auto');
  ga('send', 'pageview');
  </script>
  <link rel="stylesheet" type="text/css" href="style.css" />
  <style>
.bio {
        font-size:      95%;
        text-align:     justify;
}
.biblio {
        margin:         0.5em;
        font-size:      110%;
        line-height:    130%;
}
.center {
        text-align:     center;
}
td {
        padding:        0.5em 1em 0.5em 1em;
        vertical-align: top;
}
#toc h1 {
        font-size:      95%;
        font-weight:    normal;
}
hr {
        border:         0;
        border-top:     thin solid #ccc
}
  </style>
</head>
<body>
<table><tr>
<td>
  <a href='http://www.informit.com/store/go-programming-language-9780134190440'><img border='1' src="cover.png" height='600'/></a>
  <br/>
  <div style='text-align: center'>
  <a href='http://www.amazon.com/dp/0134190440'><img border='0' width='150' src="buyfromamazon.png"/></a>
  &nbsp;&nbsp;&nbsp;
  <a href='http://www.informit.com/store/go-programming-language-9780134190440'/><img border='0' height='26' src="informit.png"/></a>
  &nbsp;&nbsp;&nbsp;
  <a href='http://www.barnesandnoble.com/w/1121601944'><img border='0' width='150' src="barnesnoble.png"/></a>
  </div>
</br>
</td>
<td width='500'>
<h1 class='center'>The Go Programming Language</h1>
<p class='biblio center'>
Alan A. A. Donovan &middot; Brian W. Kernighan<br/>
Published Oct 26, 2015 in paperback and Nov 20 in e-book<br/>
Addison-Wesley; 380pp; ISBN:&nbsp;978-0134190440<br/>
<tt>authors</tt><tt>&#0064;</tt><tt>gopl.io</tt>
</p>

<!-- Table of Contents -->
<div id='toc'>
<table><tr>
<td>
<h1>Contents [<a href='ch1.pdf'/>PDF</a>]</h1>
<h1>Preface  [<a href='ch1.pdf'/>PDF</a>]</h1>
<h1>1. Tutorial [<a href='ch1.pdf'/>PDF</a>]</h1>
<h1>2. Program Structure</h1>
<h1>3. Basic Data Types</h1>
<h1>4. Composite Types</h1>
<h1>5. Functions</h1>
<h1>6. Methods</h1>
</td>
<td>
<h1>7. Interfaces</h1>
<h1>8. Goroutines and Channels</h1>
<h1>9. Concurrency with Shared Variables</h1>
<h1>10. Packages and the Go Tool</h1>
<h1>11. Testing</h1>
<h1>12. Reflection</h1>
<h1>13. Low-Level Programming</h1>
<h1>Index  [<a href='ch1.pdf'/>PDF</a>]</h1>
</td>
</tr>
<tr>
<td colspan='2'>
<h1>
  <a href='https://github.com/adonovan/gopl.io/'>Source code</a>&nbsp;&nbsp;|&nbsp;&nbsp;
  <a href='reviews.html'>Reviews</a>&nbsp;&nbsp;|&nbsp;&nbsp;
  <a href='translations.html'>Translations</a>&nbsp;&nbsp;|&nbsp;&nbsp;
  <a href='errata.html'>Errata</a>
</h1>
</td>
</tr>
</table>
</div>

<p class="bio">
Alan Donovan is a Staff Engineer in Google's infrastructure division,
specializing in software development tools.  Since 2012, he has been
working on the Go team, designing libraries and tools for static
analysis.  He is the author of the
<a href='http://golang.org/s/oracle-user-manual'><code>oracle</code></a>,
<a href='http://golang.org/lib/godoc/analysis/help.html'><code>godoc -analysis</code></a>,
<a href='https://github.com/golang/tools/blob/master/refactor/eg/eg.go'><code>eg</code></a>,
and <a href='https://github.com/golang/tools/blob/master/refactor/rename/rename.go'><code>gorename</code></a> tools.
</p>

<p class="bio">
Brian Kernighan was in the Computing Science Research center at Bell
Labs until 2000, where he worked on languages and tools for Unix.  He
is now a professor in the Computer Science Department at Princeton.
He is the co-author of several books, including
<a href='http://www.amazon.com/dp/0131103628?tracking_id=disfordig-20'>The C Programming Language</a> and
<a href='http://www.amazon.com/dp/020161586X?tracking_id=disfordig-20'>The Practice of Programming</a>.

</td>
</tr></table>
</body>
</html>
%!s(int64=4154)%