GolangWeb表单验证技巧解析

func handleRegister(w http.ResponseWriter, r *http.Request) {
    if r.Method != "POST" {
        http.Error(w, "只允许POST请求", http.StatusMethodNotAllowed)
        return
    }
// 解析表单数据
err := r.ParseForm()
if err != nil {
    http.Error(w, "解析表单失败", http.StatusBadRequest)
    return
}

username := r.FormValue("username")
email := r.FormValue("email")

var errors []string

if username == "" {
    errors = append(errors, "用户名不能为空")
}

if email == "" {
    errors = append(errors, "邮箱不能为空")
} else if !isValidEmail(email) {
    errors = append(errors, "邮箱格式不正确")
}

if len(errors) > 0 {
    // 返回错误信息（可渲染到模板）
    w.WriteHeader(http.StatusBadRequest)
    fmt.Fprintln(w, "验证失败：")
    for _, e := range errors {
        fmt.Fprintf(w, "- %s\n", e)
    }
    return
}

// 验证通过，继续处理逻辑
fmt.Fprintln(w, "注册成功")
}
// 简单邮箱格式检查
func isValidEmail(email string) bool {
re := regexp.MustCompile(^[a-zA-Z0-9._%+-]+@[a-zA-Z0-9.-]+\.[a-zA-Z]{2,}$)
return re.MatchString(email)
}

import (
    "github.com/go-playground/validator/v10"
)
type UserForm struct {
Username string validate:"required,min=3,max=32"
Email    string validate:"required,email"
Age      int    validate:"gte=0,lte=150"
}
var validate *validator.Validate
func init() {
validate = validator.New()
}
func handleRegisterWithValidator(w http.ResponseWriter, r *http.Request) {
if r.Method != "POST" {
http.Error(w, "只允许POST请求", http.StatusMethodNotAllowed)
return
}
err := r.ParseForm()
if err != nil {
    http.Error(w, "解析表单失败", http.StatusBadRequest)
    return
}

form := UserForm{
    Username: r.FormValue("username"),
    Email:    r.FormValue("email"),
}

// 注意：Age需要转换为int
ageStr := r.FormValue("age")
if ageStr != "" {
    age, _ := strconv.Atoi(ageStr)
    form.Age = age
}

// 执行验证
err = validate.Struct(form)
if err != nil {
    var errors []string
    for _, err := range err.(validator.ValidationErrors) {
        errors = append(errors, fmt.Sprintf("%s字段不符合规则：%v", err.Field(), err.Tag()))
    }
    w.WriteHeader(http.StatusBadRequest)
    for _, e := range errors {
        fmt.Fprintln(w, e)
    }
    return
}

fmt.Fprintln(w, "验证通过")
}

  

  

  

  注册

{{if .Errors}}

{{range .Errors}}
{{.}}
{{end}}

{{end}}