gin表单验证struct tag

本文是对 validate tag not working in ShouldBindWith 的回答。

有人提了这么一个问题：

package main

import (
	"log"
	"net/http"

	"github.com/gin-gonic/gin"
	"github.com/gin-gonic/gin/binding"
)

// MyStruct ..
type MyStruct struct {
	Order string `form:"order,default=DESC" validate:"omitempty,oneof=ASC DESC"`
}

func startPage(c *gin.Context) {
	var person MyStruct
	if c.ShouldBindWith(&person, binding.Query) == nil {
		log.Println("====== Only Bind By Query String ======")
		log.Println(person.Order)
		c.String(http.StatusOK, "Success")
		return
		// log.Println(person.Address)
	}
	c.String(http.StatusBadRequest, "Failed")
	return
}

func main() {

	route := gin.Default()
	route.Any("/testing", startPage)
	route.Run(":8085