golang之数据校验的实现代码示例

目前大都是使用 validator

安装

go get gopkg.in/go-playground/validator.v9

原理

当然只能通过反射来实现了，之前写过一篇反射的文章 golang之反射和断言 ，里面有写到怎么通过反射获取struct tag。

读取struct tag之后就是对里面的标识符进行识别，然后进行验证了。具体可以去看源码。

demo

简单使用：

package main

import (
"fmt"
"gopkg.in/go-playground/validator.v9"
)

// User contains user information
type UserInfo struct {
FirstName  string  `validate:"required"`
LastName  string  `validate:"required"`
Age   uint8  `validate:"gte=0,lte=100"`
Email   string  `validate:"required,email"`
}

func main() {
validate := validator.New()
user := &UserInfo{
FirstName:  "Badger",
LastName:  "Smith",
Age:   105,
Email:   "",
}
err := validate.Struct(user)
if err != nil {
for _, err := range err.(validator.ValidationErrors) {
fmt.Println(err)
}
return
}
fmt.Println("success")
}

输出：

Key: 'UserInfo.Age' Error:Field validation for 'Age' failed on the 'lte' tag
Key: 'UserInfo.Email' Error:Field validation for 'Email' failed on the 'required' tag

其它类型可以参照文档 https://godoc.org/gopkg.in/go-playground/validator.v9

几个例子：

1.IP
type UserInfo struct {
Ip    string  `validate:"ip"`
}
2.数字
type UserInfo struct {
Number float32 `validate:"numeric"`
}
3.最大值
type UserInfo struct {
Number float32 `validate:"max=10"`
}
4.最小值
type UserInfo struct {
Number float32 `validate:"min=10"`
}

自定义验证函数

package main

import (
"fmt"
"gopkg.in/go-playground/validator.v9"
"unicode/utf8"
)

// User contains user information
type UserInfo struct {
Name   string  `validate:"checkName"`
Number float32 `validate:"numeric"`
}
// 自定义验证函数
func checkName(fl validator.FieldLevel) bool {
count := utf8.RuneCountInString(fl.Field().String())
fmt.Printf("length: %v \n", count)
if count > 5 {
return false
}
return true
}

func main() {
validate := validator.New()
//注册自定义函数，与struct tag关联起来
err := validate.RegisterValidation("checkName", checkName)
user := &UserInfo{
Name:   "我是中国人，我爱自己的祖国",
Number:   23,
}
err = validate.Struct(user)
if err != nil {
for _, err := range err.(validator.ValidationErrors) {
fmt.Println(err)
}
return
}
fmt.Println("success")
}

以上就是本文的全部内容，希望对大家的学习有所帮助