<form method="POST" action="mygo">
 <input type=hidden name="emails[]" value="email1@email.com">
 <input type=hidden name="emails[]" value="email2@email.com">
 <input type=hidden name="emails[]" value="email3@email.com">
</form>

<form method="POST" action="mygo">
 <input type=hidden name="emails" value="email1@email.com">
 <input type=hidden name="emails" value="email2@email.com">
 <input type=hidden name="emails" value="email3@email.com">
</form>

func main() {
// ...
    router.POST("mygo",parseFunc)
}

func mygo(c *gin.Context) {
  c.Request.ParseForm()
  log.Printf("%v",c.Request.PostForm["emails"]) // ""
  log.Printf("%v",c.PostForm("emails") // "email3@email.com"
}