Go Web 开发核心理论：HTTP、数据库与模板 | 极客日志

Go Web 开发核心理论：HTTP、数据库与模板 | 极客日志

import (
    _ "github.com/go-sql-driver/mysql"
    "github.com/jmoiron/sqlx"
)

DB, err := sqlx.Open("mysql", "root:1234@tcp(localhost:3306)/goweb?parseTime=true&loc=Local")
if err != nil {
    // handle error
}
DB.Ping()

// 语句定义
queryCreate := "insert into user (id,name) values (?,?)"
queryDelete := "delete from user where id =?"
queryUpdate := "update user set name=? where id=?"
queryQuery := "select * from user"

// 执行
// 增：DB.Exec(queryCreate, 1, "白小纯")
// 删：DB.Exec(queryDelete, 1)
// 改：DB.Exec(queryUpdate, "夜藏", 1)
// 查：rows, err := DB.Query(queryQuery)
// for rows.Next() { rows.Scan(&id, &name) }

func serv(w http.ResponseWriter, r *http.Request) {
    // Cookie 赋值
    cookie := &http.Cookie{
        Name:  "session_id",
        Value: "cookie",
        Expires: time.Now().Add(time.Second),
    }
    http.SetCookie(w, cookie)

    // 获取单个 Cookie
    c, _ := r.Cookie("session_id")
    fmt.Fprintln(w, c.Name, c.Value, c.Expires)

    // 循环获取 Cookie
    cs := r.Cookies()
    for n, co := range cs {
        fmt.Fprintln(w, n, co.Name)
    }
}

// 后端界面
func temp(w http.ResponseWriter, r *http.Request) {
    add := template.FuncMap{"add": Add}
    t := template.New("index").Funcs(add)
    t, _ = t.ParseFiles("new_add")
    t.Execute(w, nil)
}

<form action="upload" enctype="multipart/form-data" method="post">
  上传照片：<input type="file" name="photo">
</form>

func upload(w http.ResponseWriter, r *http.Request) {
    f, _, _ := r.FormFile("photo")
    b, _ := io.ReadAll(f)
    err := ioutil.WriteFile("/tmp/photo", b, 0777)
    if err != nil {
        fmt.Println("失败")
    }
}

<a href="download?filename=file.png">点击我下载</a>

func download(w http.ResponseWriter, r *http.Request) {
    name := r.FormValue("filename")
    ReadFile, _ := os.ReadFile("address" + name)
    h := w.Header()
    h.Set("Content-Type", "application/octet-stream")
    h.Set("Content-Disposition", "attachment; filename=photo")
    fmt.Fprintln(w, ReadFile)
}

type myStruct struct{}

func (m myStruct) ServeHTTP(w http.ResponseWriter, r *http.Request) {}

func main() {
    s := http.Server{
        Addr:    "localhost:8888",
        Handler: myStruct{},
    }
    s.ListenAndServe()
}

func Test(w http.ResponseWriter, r *http.Request) {}

func main() {
    server := http.Server{
        Addr: "localhost:8888",
    }
    http.HandleFunc("/url", Test)
    server.ListenAndServe()
}