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 mainimport ( "fmt" "gopkg.in/go-playground/validator.v9")// User contains user informationtype 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.IPtype 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 mainimport ( "fmt" "gopkg.in/go-playground/validator.v9" "unicode/utf8")// User contains user informationtype 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，也希望大家多多支持。