// Copyright 2015 The Go Authors. All rights reserved. // Use of this source code is governed by a BSD-style // license that can be found in the LICENSE file. package template_test import ( "fmt" "html/template" "log" "os" "strings" ) func Example() { const tpl = ` {{.Title}} {{range .Items}}
{{ . }}
{{else}}
no rows
{{end}} ` check := func(err error) { if err != nil { log.Fatal(err) } } t, err := template.New("webpage").Parse(tpl) check(err) data := struct { Title string Items []string }{ Title: "My page", Items: []string{ "My photos", "My blog", }, } err = t.Execute(os.Stdout, data) check(err) noItems := struct { Title string Items []string }{ Title: "My another page", Items: []string{}, } err = t.Execute(os.Stdout, noItems) check(err) // Output: // // // // // My page // // //
My photos
My blog
// // // // // // // My another page // // //
no rows
// // } func Example_autoescaping() { check := func(err error) { if err != nil { log.Fatal(err) } } t, err := template.New("foo").Parse(`{{define "T"}}Hello, {{.}}!{{end}}`) check(err) err = t.ExecuteTemplate(os.Stdout, "T", "") check(err) // Output: // Hello, <script>alert('you have been pwned')</script>! } func Example_escape() { const s = `"Fran & Freddie's Diner" ` v := []any{`"Fran & Freddie's Diner"`, ' ', ``} fmt.Println(template.HTMLEscapeString(s)) template.HTMLEscape(os.Stdout, []byte(s)) fmt.Fprintln(os.Stdout, "") fmt.Println(template.HTMLEscaper(v...)) fmt.Println(template.JSEscapeString(s)) template.JSEscape(os.Stdout, []byte(s)) fmt.Fprintln(os.Stdout, "") fmt.Println(template.JSEscaper(v...)) fmt.Println(template.URLQueryEscaper(v...)) // Output: // "Fran & Freddie's Diner" <tasty@example.com> // "Fran & Freddie's Diner" <tasty@example.com> // "Fran & Freddie's Diner"32<tasty@example.com> // \"Fran \u0026 Freddie\'s Diner\" \u003Ctasty@example.com\u003E // \"Fran \u0026 Freddie\'s Diner\" \u003Ctasty@example.com\u003E // \"Fran \u0026 Freddie\'s Diner\"32\u003Ctasty@example.com\u003E // %22Fran+%26+Freddie%27s+Diner%2232%3Ctasty%40example.com%3E } func ExampleTemplate_Delims() { const text = "<<.Greeting>> {{.Name}}" data := struct { Greeting string Name string }{ Greeting: "Hello", Name: "Joe", } t := template.Must(template.New("tpl").Delims("<<", ">>").Parse(text)) err := t.Execute(os.Stdout, data) if err != nil { log.Fatal(err) } // Output: // Hello {{.Name}} } // The following example is duplicated in text/template; keep them in sync. func ExampleTemplate_block() { const ( master = `Names:{{block "list" .}}{{"\n"}}{{range .}}{{println "-" .}}{{end}}{{end}}` overlay = `{{define "list"}} {{join . ", "}}{{end}} ` ) var ( funcs = template.FuncMap{"join": strings.Join} guardians = []string{"Gamora", "Groot", "Nebula", "Rocket", "Star-Lord"} ) masterTmpl, err := template.New("master").Funcs(funcs).Parse(master) if err != nil { log.Fatal(err) } overlayTmpl, err := template.Must(masterTmpl.Clone()).Parse(overlay) if err != nil { log.Fatal(err) } if err := masterTmpl.Execute(os.Stdout, guardians); err != nil { log.Fatal(err) } if err := overlayTmpl.Execute(os.Stdout, guardians); err != nil { log.Fatal(err) } // Output: // Names: // - Gamora // - Groot // - Nebula // - Rocket // - Star-Lord // Names: Gamora, Groot, Nebula, Rocket, Star-Lord }