github.com/hlts2/go@v0.0.0-20170904000733-812b34efaed8/src/html/template/example_test.go (about)

     1  // Copyright 2015 The Go Authors. All rights reserved.
     2  // Use of this source code is governed by a BSD-style
     3  // license that can be found in the LICENSE file.
     4  
     5  package template_test
     6  
     7  import (
     8  	"fmt"
     9  	"html/template"
    10  	"log"
    11  	"os"
    12  	"strings"
    13  )
    14  
    15  func Example() {
    16  	const tpl = `
    17  <!DOCTYPE html>
    18  <html>
    19  	<head>
    20  		<meta charset="UTF-8">
    21  		<title>{{.Title}}</title>
    22  	</head>
    23  	<body>
    24  		{{range .Items}}<div>{{ . }}</div>{{else}}<div><strong>no rows</strong></div>{{end}}
    25  	</body>
    26  </html>`
    27  
    28  	check := func(err error) {
    29  		if err != nil {
    30  			log.Fatal(err)
    31  		}
    32  	}
    33  	t, err := template.New("webpage").Parse(tpl)
    34  	check(err)
    35  
    36  	data := struct {
    37  		Title string
    38  		Items []string
    39  	}{
    40  		Title: "My page",
    41  		Items: []string{
    42  			"My photos",
    43  			"My blog",
    44  		},
    45  	}
    46  
    47  	err = t.Execute(os.Stdout, data)
    48  	check(err)
    49  
    50  	noItems := struct {
    51  		Title string
    52  		Items []string
    53  	}{
    54  		Title: "My another page",
    55  		Items: []string{},
    56  	}
    57  
    58  	err = t.Execute(os.Stdout, noItems)
    59  	check(err)
    60  
    61  	// Output:
    62  	// <!DOCTYPE html>
    63  	// <html>
    64  	// 	<head>
    65  	// 		<meta charset="UTF-8">
    66  	// 		<title>My page</title>
    67  	// 	</head>
    68  	// 	<body>
    69  	// 		<div>My photos</div><div>My blog</div>
    70  	// 	</body>
    71  	// </html>
    72  	// <!DOCTYPE html>
    73  	// <html>
    74  	// 	<head>
    75  	// 		<meta charset="UTF-8">
    76  	// 		<title>My another page</title>
    77  	// 	</head>
    78  	// 	<body>
    79  	// 		<div><strong>no rows</strong></div>
    80  	// 	</body>
    81  	// </html>
    82  
    83  }
    84  
    85  func Example_autoescaping() {
    86  	check := func(err error) {
    87  		if err != nil {
    88  			log.Fatal(err)
    89  		}
    90  	}
    91  	t, err := template.New("foo").Parse(`{{define "T"}}Hello, {{.}}!{{end}}`)
    92  	check(err)
    93  	err = t.ExecuteTemplate(os.Stdout, "T", "<script>alert('you have been pwned')</script>")
    94  	check(err)
    95  	// Output:
    96  	// Hello, &lt;script&gt;alert(&#39;you have been pwned&#39;)&lt;/script&gt;!
    97  }
    98  
    99  func Example_escape() {
   100  	const s = `"Fran & Freddie's Diner" <tasty@example.com>`
   101  	v := []interface{}{`"Fran & Freddie's Diner"`, ' ', `<tasty@example.com>`}
   102  
   103  	fmt.Println(template.HTMLEscapeString(s))
   104  	template.HTMLEscape(os.Stdout, []byte(s))
   105  	fmt.Fprintln(os.Stdout, "")
   106  	fmt.Println(template.HTMLEscaper(v...))
   107  
   108  	fmt.Println(template.JSEscapeString(s))
   109  	template.JSEscape(os.Stdout, []byte(s))
   110  	fmt.Fprintln(os.Stdout, "")
   111  	fmt.Println(template.JSEscaper(v...))
   112  
   113  	fmt.Println(template.URLQueryEscaper(v...))
   114  
   115  	// Output:
   116  	// &#34;Fran &amp; Freddie&#39;s Diner&#34; &lt;tasty@example.com&gt;
   117  	// &#34;Fran &amp; Freddie&#39;s Diner&#34; &lt;tasty@example.com&gt;
   118  	// &#34;Fran &amp; Freddie&#39;s Diner&#34;32&lt;tasty@example.com&gt;
   119  	// \"Fran & Freddie\'s Diner\" \x3Ctasty@example.com\x3E
   120  	// \"Fran & Freddie\'s Diner\" \x3Ctasty@example.com\x3E
   121  	// \"Fran & Freddie\'s Diner\"32\x3Ctasty@example.com\x3E
   122  	// %22Fran+%26+Freddie%27s+Diner%2232%3Ctasty%40example.com%3E
   123  
   124  }
   125  
   126  // The following example is duplicated in text/template; keep them in sync.
   127  
   128  func ExampleTemplate_block() {
   129  	const (
   130  		master  = `Names:{{block "list" .}}{{"\n"}}{{range .}}{{println "-" .}}{{end}}{{end}}`
   131  		overlay = `{{define "list"}} {{join . ", "}}{{end}} `
   132  	)
   133  	var (
   134  		funcs     = template.FuncMap{"join": strings.Join}
   135  		guardians = []string{"Gamora", "Groot", "Nebula", "Rocket", "Star-Lord"}
   136  	)
   137  	masterTmpl, err := template.New("master").Funcs(funcs).Parse(master)
   138  	if err != nil {
   139  		log.Fatal(err)
   140  	}
   141  	overlayTmpl, err := template.Must(masterTmpl.Clone()).Parse(overlay)
   142  	if err != nil {
   143  		log.Fatal(err)
   144  	}
   145  	if err := masterTmpl.Execute(os.Stdout, guardians); err != nil {
   146  		log.Fatal(err)
   147  	}
   148  	if err := overlayTmpl.Execute(os.Stdout, guardians); err != nil {
   149  		log.Fatal(err)
   150  	}
   151  	// Output:
   152  	// Names:
   153  	// - Gamora
   154  	// - Groot
   155  	// - Nebula
   156  	// - Rocket
   157  	// - Star-Lord
   158  	// Names: Gamora, Groot, Nebula, Rocket, Star-Lord
   159  }