go_template.md

Go template学习样例

1. 简单的模板

package main

import (
	"os"
	"text/template"
)

type Inventory struct {
	Material string
	Count    uint
}

func main() {
	tpt := `{{.Count}} items are made of {{.Material}}\n`

	sweaters := Inventory{"wool", 17}

	tmpl, err := template.New("test").Parse(tpt)
	if err != nil {
		panic(err)
	}

	if err = tmpl.Execute(os.Stdout, sweaters); err != nil {
		panic(err)
	}
}

2. Array遍历

package main

import (
	"html/template"
	"os"
)

type EntetiesClass struct {
	Name  string
	Value int32
}

// In the template, we use rangeStruct to turn our struct values
// into a slice we can iterate over
const htmlTemplate = `
{{range $index, $element := .}}
	{{$index}}
		{{range $element}}
			{{.Name}} {{.Value}}
		{{end}}
{{end}}
`

func main() {
	data := map[string][]EntetiesClass{
		"Yoga":    {{"Yoga1", 13}, {"Yoga2", 15}},
		"Pilates": {{"Pilates1", 3}, {"Pilates2", 6}, {"Pilates3", 9}},
	}

	t := template.New("t")
	t, err := t.Parse(htmlTemplate)
	if err != nil {
		panic(err)
	}

	err = t.Execute(os.Stdout, data)
	if err != nil {
		panic(err)
	}
}

3. Map遍历

3.1 Range 遍历

按照map的rang来进行访问

package main

import (
    "fmt"
    "os"
    "text/template"

)

func main() {
    fmt.Println("Hello, playground")

    const templ = `Here is what they said
    {{ range $key, $value := . }}
        {{ $key }}:{{ $value }}
    {{end}}
    `
    x := map[string]string{
        "Danny": "The guy really talked about my first time out with you",
        "Doug":  "Well he said I'm really amazing, I did not believe at first",

    }

    t, err := template.New("index.html").Parse(templ)
    if err != nil {
        fmt.Println("Could not parse template:", err)
        return

    }
    t.Execute(os.Stdout, x)

}

3.2 Key 遍历

按照map的key来进行访问

package main

import (
	"os"
	"text/template"
)

// show how to get map key
func main() {

	// map value:	{{index .mymap "key"}}
	tpt := `
		{{if eq "hello" (index .mymap "key")}} hello {{else}} not hello {{end}} 
	`

	t := template.Must(template.New("").Parse(tpt))

	value := map[string]interface{}{"mymap": map[string]string{"key": "value"}}

	t.Execute(os.Stdout, value)
}

参考：

1. Access a map value using a variable key in a Go template

2. How to get map value by key without range action (htm/text templates)? Golang