func RegisterCustomValidators(validate *validator.Validate) error

validate := validator.New()
if err := xVaild.RegisterCustomValidators(validate); err != nil {
    log.Fatal("验证器注册失败:", err)
}

type Request struct {
    Website string `json:"website" binding:"required,strict_url"`
}

type Request struct {
    ID string `json:"id" binding:"required,strict_uuid"`
}

type Request struct {
    Username string `json:"username" binding:"required,alphanum_underscore"`
}

type Request struct {
    // 中国大陆手机号
    Phone string `json:"phone" binding:"required,regexp=^1[3-9]\\d{9}$"`
    // 邮政编码
    ZipCode string `json:"zip_code" binding:"required,regexp=^\\d{6}$"`
}

type Request struct {
    // 状态：1=启用, 2=禁用, 3=待审核
    Status int `json:"status" binding:"required,enum_int=1 2 3"`
}

type Request struct {
    // 角色：admin, user, guest
    Role string `json:"role" binding:"required,enum_string=admin user guest"`
}

type Request struct {
    // 折扣：0.5, 0.7, 0.8, 0.9, 1.0
    Discount float64 `json:"discount" binding:"required,enum_float=0.5 0.7 0.8 0.9 1.0"`
}

type CreateProductRequest struct {
    // 商品名称：字母数字下划线
    Code string `json:"code" label:"商品编码" binding:"required,alphanum_underscore,min=4,max=32"`

    // 商品链接：严格 URL
    Link string `json:"link" label:"商品链接" binding:"omitempty,strict_url"`

    // 商品状态：枚举值
    Status int `json:"status" label:"商品状态" binding:"required,enum_int=1 2 3"`

    // SKU 编码：正则验证
    SKU string `json:"sku" label:"SKU编码" binding:"required,regexp=^SKU-\\d{8}$"`
}

type Func func(fl validator.FieldLevel) bool

package validator

import (
    "strings"
    "github.com/go-playground/validator/v10"
)

// ValidatePrefix 验证字符串是否以指定前缀开头
// 使用: binding:"prefix=SKU-"
func ValidatePrefix(fl validator.FieldLevel) bool {
    // 获取参数（前缀）
    prefix := fl.Param()
    if prefix == "" {
        return false
    }

    // 获取字段值
    value := fl.Field().String()

    return strings.HasPrefix(value, prefix)
}

package validator

import (
    "strconv"
    "strings"
    "github.com/go-playground/validator/v10"
)

// ValidateBetween 验证整数是否在指定范围内
// 使用: binding:"between=1-100"
func ValidateBetween(fl validator.FieldLevel) bool {
    // 解析参数 "min-max"
    param := fl.Param()
    parts := strings.Split(param, "-")
    if len(parts) != 2 {
        return false
    }

    min, err1 := strconv.ParseInt(parts[0], 10, 64)
    max, err2 := strconv.ParseInt(parts[1], 10, 64)
    if err1 != nil || err2 != nil {
        return false
    }

    // 获取字段值
    value := fl.Field().Int()

    return value >= min && value <= max
}

package validator

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

// ValidateConfirmPassword 验证确认密码是否与密码一致
// 使用: binding:"confirm_password=Password"
func ValidateConfirmPassword(fl validator.FieldLevel) bool {
    // 获取参数（要比较的字段名）
    fieldName := fl.Param()
    if fieldName == "" {
        return false
    }

    // 获取父结构体中的目标字段
    parent := fl.Parent()
    targetField := parent.FieldByName(fieldName)
    if !targetField.IsValid() {
        return false
    }

    // 比较两个字段的值
    return fl.Field().String() == targetField.String()
}

type RegisterRequest struct {
    Password        string `json:"password" label:"密码" binding:"required,min=8"`
    ConfirmPassword string `json:"confirm_password" label:"确认密码" binding:"required,confirm_password=Password"`
}

package startup

import (
    "github.com/gin-gonic/gin/binding"
    "github.com/go-playground/validator/v10"
)

// RegisterCustomValidators 注册项目自定义验证器
// 在 xReg.Register() 之后、路由注册之前调用
func RegisterCustomValidators() {
    if v, ok := binding.Validator.Engine().(*validator.Validate); ok {
        // 注册自己的验证器
        _ = v.RegisterValidation("prefix", ValidatePrefix)
        _ = v.RegisterValidation("between", ValidateBetween)
        _ = v.RegisterValidation("confirm_password", ValidateConfirmPassword)
    }
}

func main() {
    ctx := context.Background()

    // 1. 初始化基础库（已注册内置验证器）
    reg := xReg.Register(ctx)

    // 2. 注册项目自定义验证器
    startup.RegisterCustomValidators()

    // 3. 注册路由
    router.RegisterRouter(reg.Serve)

    // 4. 启动服务
    _ = reg.Serve.Run(":8080")
}

### 添加中文错误消息

在 `messages.go` 中添加自定义验证器的错误消息：

```go title="validator/messages.go"
var CustomValidationMessages = map[string]string{
    "prefix":           "必须以 %s 开头",
    "between":          "必须在 %s 范围内",
    "confirm_password": "与密码不一致",
}

// 注册自定义验证器的翻译
_ = v.RegisterTranslation("prefix", trans, func(ut ut.Translator) error {
    return ut.Add("prefix", "{0}必须以 {1} 开头", true)
}, func(ut ut.Translator, fe validator.FieldError) string {
    t, _ := ut.T("prefix", fe.Field(), fe.Param())
    return t
})