example_test.go

Documentation: html/template

		 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" <[email protected]>`
	 101  	v := []interface{}{`"Fran & Freddie's Diner"`, ' ', `<[email protected]>`}
	 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;[email protected]&gt;
	 117  	// &#34;Fran &amp; Freddie&#39;s Diner&#34; &lt;[email protected]&gt;
	 118  	// &#34;Fran &amp; Freddie&#39;s Diner&#34;32&lt;[email protected]&gt;
	 119  	// \"Fran \u0026 Freddie\'s Diner\" \[email protected]\u003E
	 120  	// \"Fran \u0026 Freddie\'s Diner\" \[email protected]\u003E
	 121  	// \"Fran \u0026 Freddie\'s Diner\"32\[email protected]\u003E
	 122  	// %22Fran+%26+Freddie%27s+Diner%2232%3Ctasty%40example.com%3E
	 123  
	 124  }
	 125  
	 126  func ExampleTemplate_Delims() {
	 127  	const text = "<<.Greeting>> {{.Name}}"
	 128  
	 129  	data := struct {
	 130  		Greeting string
	 131  		Name		 string
	 132  	}{
	 133  		Greeting: "Hello",
	 134  		Name:		 "Joe",
	 135  	}
	 136  
	 137  	t := template.Must(template.New("tpl").Delims("<<", ">>").Parse(text))
	 138  
	 139  	err := t.Execute(os.Stdout, data)
	 140  	if err != nil {
	 141  		log.Fatal(err)
	 142  	}
	 143  
	 144  	// Output:
	 145  	// Hello {{.Name}}
	 146  }
	 147  
	 148  // The following example is duplicated in text/template; keep them in sync.
	 149  
	 150  func ExampleTemplate_block() {
	 151  	const (
	 152  		master	= `Names:{{block "list" .}}{{"\n"}}{{range .}}{{println "-" .}}{{end}}{{end}}`
	 153  		overlay = `{{define "list"}} {{join . ", "}}{{end}} `
	 154  	)
	 155  	var (
	 156  		funcs		 = template.FuncMap{"join": strings.Join}
	 157  		guardians = []string{"Gamora", "Groot", "Nebula", "Rocket", "Star-Lord"}
	 158  	)
	 159  	masterTmpl, err := template.New("master").Funcs(funcs).Parse(master)
	 160  	if err != nil {
	 161  		log.Fatal(err)
	 162  	}
	 163  	overlayTmpl, err := template.Must(masterTmpl.Clone()).Parse(overlay)
	 164  	if err != nil {
	 165  		log.Fatal(err)
	 166  	}
	 167  	if err := masterTmpl.Execute(os.Stdout, guardians); err != nil {
	 168  		log.Fatal(err)
	 169  	}
	 170  	if err := overlayTmpl.Execute(os.Stdout, guardians); err != nil {
	 171  		log.Fatal(err)
	 172  	}
	 173  	// Output:
	 174  	// Names:
	 175  	// - Gamora
	 176  	// - Groot
	 177  	// - Nebula
	 178  	// - Rocket
	 179  	// - Star-Lord
	 180  	// Names: Gamora, Groot, Nebula, Rocket, Star-Lord
	 181  }
	 182
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