web编程
web编程基础
web的工作方式
http协议介绍
- http请求体
- http响应体
Web程序开发
- 基于“net/http”封装的web服务相关的功能
- 使用简单
func sayhelloName(w http.ResponseWriter,r *http.Request) {
r.ParseForm() //参数解析
fmt.Printf("r.Form:%v\n",r.Form)
fmt.Printf("Path:%v\n",r.URL.Path)
fmt.Printf("Schema:%v\n",r.URL.Scheme)
fmt.Printf("r.Form[url_long]:%v\n",r.Form["url_long"])
for k,v := range r.Form{
fmt.Printf("key=%v\n",k)
fmt.Printf("val=%v\n",strings.Join(v,""))
}
fmt.Fprintf(w,"hello")
}
func main() {
http.HandleFunc("/",sayhelloName)
err := http.ListenAndServe(":9090",nil)
if err != nil {
log.Fatal("ListenAndServer:",err)
}
}
golang web服务工作方式
表单提交
-
通过
<form></form>
扩起来的区域,允许用户提交数据 - 用户登录验证小例子
- login.html
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Login</title>
</head>
<body>
<form action="/login" method="POST">
<div>
<span>用户名:</span>
<input type="text" name="username">
</div>
<div>
<span>密码:</span>
<input type="text" name="password">
</div>
<div>
<input type="submit" value="登录">
</div>
</form>
</body>
</html>
- AuthFunc.go
func loginFunc(w http.ResponseWriter,r *http.Request) {
if r.Method == "GET" {
data,err := ioutil.ReadFile("./login.html")
if err != nil {
http.Redirect(w,r,"/404.html",http.StatusNotFound)
fmt.Errorf("read file faild:err:%v\n",err)
return
}
w.Write(data)
}else if r.Method == "POST" {
r.ParseForm()
username := r.FormValue("username")
password := r.FormValue("password")
if username == "admin" && password == "admin" {
fmt.Fprintf(w,"login success")
}else {
fmt.Fprintf(w,"username or password error")
}
}
}
func main() {
http.HandleFunc("/login",loginFunc)
err := http.ListenAndServe(":9090",nil)
if err != nil {
log.Fatal("ListenAndServer:",err)
}
}
模板介绍与使用
模板替换
{{}}
来包含需要在渲染时被替换的字段,{{.}}
表示当前对象
通过{{.FieldName}}
来访问对象的属性
- demo.go
var (
t *template.Template
)
type User struct {
Name string
Age int
}
func initTemplate() (err error){
//加载模板
t, err = template.ParseFiles("./index.html")
if err != nil {
fmt.Println("parse file error:",err)
return
}
return
}
func handleUserInfo(w http.ResponseWriter,r *http.Request) {
var user User = User{
Name: "wanghui",
Age: 20,
}
t.Execute(w,user)
}
func main() {
err := initTemplate()
if err != nil {
return
}
http.HandleFunc("/user/info",handleUserInfo)
err = http.ListenAndServe(":9090",nil)
if err != nil {
fmt.Errorf("http start error %v\n",err)
return
}
}
- index.html
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Login</title>
</head>
<body>
<form action="/login" method="POST">
<div>
<span>用户名:{{ .Name }}</span>
</div>
<div>
<span>年龄:{{ .Age }}</span>
</div>
</form>
</body>
</html>
if判断
- index.html
<div>
<span>用户名:{{ .Name }}</span>
</div>
<div>
<span>年龄:{{ .Age }}</span>
</div>
<div>
{{ if gt .Age 18 }}
<p>Hello old man</p>
{{ else }}
<p>hello young man</p>
{{ end }}
</div>
with用法
为了简化结构体嵌套的问题
- index.html
<body>
<form action="/login" method="POST">
<div>
<span>用户名:{{ .Name }}</span>
</div>
<div>
<span>年龄:{{ .Age }}</span>
</div>
{{with .Address}}
<div>
<span>省:{{.Province}}</span>
</div>
<div>
<span>城市:{{.City}}</span>
</div>
<div>
<span>邮编:{{.Code}}</span>
</div>
{{end}}
</form>
</body>
- server.go
var (
t *template.Template
)
type Address struct {
Province string
City string
Code string
}
type User struct {
Name string
Age int
Address Address
}
func initTemplate() (err error){
//加载模板
t, err = template.ParseFiles("./index.html")
if err != nil {
fmt.Println("parse file error:",err)
return
}
return
}
func handleUserInfo(w http.ResponseWriter,r *http.Request) {
var user User = User{
Name: "wanghui",
Age: 20,
Address:Address{
Province: "gansu",
City: "zhangye",
Code: "734000",
},
}
t.Execute(w,user)
}
func main() {
err := initTemplate()
if err != nil {
return
}
http.HandleFunc("/user/info",handleUserInfo)
err = http.ListenAndServe(":9090",nil)
if err != nil {
fmt.Errorf("http start error %v\n",err)
return
}
}
range循环语法
- index.html
<body>
<form action="/login" method="POST">
{{range .}}
<div>
<span>用户名:{{ .Name }}</span>
</div>
<div>
<span>年龄:{{ .Age }}</span>
</div>
{{with .Address}}
<div>
<span>省:{{.Province}}</span>
</div>
<div>
<span>城市:{{.City}}</span>
</div>
<div>
<span>邮编:{{.Code}}</span>
</div>
<hr>
{{end}}
{{end}}
</form>
</body>
- server.go
package main
import (
"fmt"
"html/template"
"net/http"
)
var (
t *template.Template
)
type Address struct {
Province string
City string
Code string
}
type User struct {
Name string
Age int
Address Address
}
func initTemplate() (err error) {
//加载模板
t, err = template.ParseFiles("./index.html")
if err != nil {
fmt.Println("parse file error:", err)
return
}
return
}
func handleUserInfo(w http.ResponseWriter, r *http.Request) {
var users []*User
for i := 0; i < 15; i++ {
var user User = User{
Name: "wanghui",
Age: 20,
Address: Address{
Province: "gansu",
City: "zhangye",
Code: "734000",
},
}
users = append(users,&user)
}
t.Execute(w, users)
}
func main() {
err := initTemplate()
if err != nil {
return
}
http.HandleFunc("/user/info", handleUserInfo)
err = http.ListenAndServe(":9090", nil)
if err != nil {
fmt.Errorf("http start error %v\n", err)
return
}
}
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