Golang实现Web表单验证技巧

type UserForm struct {
    Name  string `validate:"required,min=2,max=20"`
    Email string `validate:"required,email"`
    Age   int    `validate:"required,gt=0,lt=120"`
}

go get github.com/go-playground/validator/v10

import "github.com/go-playground/validator/v10"

var validate *validator.Validate

func init() {
    validate = validator.New()
}

func handleUserForm(w http.ResponseWriter, r *http.Request) {
    if err := r.ParseForm(); err != nil {
        http.Error(w, "解析表单失败", 400)
        return
    }

    form := UserForm{
        Name:  r.FormValue("name"),
        Email: r.FormValue("email"),
        Age:   parseInt(r.FormValue("age")), // 自定义转换函数
    }

    if err := validate.Struct(form); err != nil {
        for _, err := range err.(validator.ValidationErrors) {
            fmt.Fprintf(w, "%s 字段验证失败: %s\n", err.Field(), err.Tag())
        }
        return
    }

    fmt.Fprintln(w, "表单验证通过")
}

package main

import (
    "github.com/gin-gonic/gin"
    "net/http"
)

type LoginInput struct {
    Username string `json:"username" binding:"required,min=3"`
    Password string `json:"password" binding:"required,min=6"`
}

func main() {
    r := gin.Default()
    r.POST("/login", func(c *gin.Context) {
        var input LoginInput
        if err := c.ShouldBind(&input); err != nil {
            c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
            return
        }
        c.JSON(http.StatusOK, gin.H{"message": "登录成功"})
    })
    r.Run(":8080")
}