php表单本身保存到数据库

Question

我的目标是形成自己，这意味着行动就是行动=“”。我有脚本的一部分，它不会保存到数据库。有人可以帮助我。这是我的代码如下。这部分代码在这里，它不会保存到数据库

if($id!="" && $username!="" && $password!="" && $firstname!="" && $lastname!="" && $email!="" && $address!="" && $month!="" && $day!="" && $year!="" && $gender!="" && $course!="" && $yr_sec!="" && $checkbox_error!="" ){
          require("session/DBConnection.php");
          $sql_insert = "INSERT INTO members(id_no, username, password, firstname, lastname, email, address,  gender, course, yr_sec)
                        VALUES('$id', '$username', '$password', '$firstname', '$lastname', '$email', '$address', '$gender', '$course', '$yr_sec')";
          mysql_query($sql_insert);

        }

当我删除if语句时，它将保存到db但验证失败。所以这就是为什么我放了一个if语句，有人可以检查这个???或者如何编写更好的方法？ 以下是完整的脚本

<?php
    require("session/DBConnection.php");
    $id = "";
    $id_error = "";
    $username = "";
    $username_error = "";
    $password ="";
    $password_error ="";
    $firstname = "";
    $firstname_error ="";
    $lastname = "";
    $lastname_error ="";
    $email ="";
    $email_error ="";
    $regEmail = "";
    $address ="";
    $address_error ="";
    $month = "";
    $month_error ="";
    $day ="";
    $day_error ="";
    $year ="";
    $year_error = "";
    $gender ="";
    $gender_error ="";
    $course = "";
    $course_error = "";
    $yr_sec ="";
    $yr_sec_error = "";
    $checkbox_error = "";
    if(isset($_POST['register'])){
        if(empty($_POST['id'])){
          $id_error = "Please Fill up ID.";
        }else{
          $id = $_POST['id'];
        }

        if(empty($_POST['username'])){
          $username_error = "Please Input Username";
        }else{
        if( 6 > mb_strlen($_POST['username']) || 20 < mb_strlen($_POST['username'])){
          $username_error = "username must be at least 6 characters.";
        }else{
          $username = $_POST['username'];
        }
        }
        if(empty($_POST['password'])){
          $password_error = "Please Input Password";
        }else{
        if( 6 > mb_strlen($_POST['password']) || 20 < mb_strlen($_POST['password'])){
          $password_error = "pasword must be at least 6 characters.";
        }else{
          $password = sha1($_POST['password']);
        }
        }

        if(empty($_POST['firstname'])){
          $firstname_error = "Please Input Firstname.";
        }else{
          $firstname = $_POST['firstname'];
        }

        if(empty($_POST['lastname'])){
        $lastname_error = "Please Input Lastname.";
        }else{
          $lastname = $_POST['lastname'];
        }

        if(empty($_POST['email'])){
          $email_error = "Please Input Email Address.";
        }else{
          $regEmail .= '/^\w+([-+.]\w+)*@\w+([-.]\w+)*\.\w+([-.]\w+)*$/';
        if(!preg_match($regEmail, $_POST['email'])){
          $email_error = "Please Enter a Valid Email Address.";
        }else{
          $email = $_POST['email'];
        }
        }

        if(empty($_POST['address'])){
          $address_error = "Please Fill up Address";
        }else{
          $address = $_POST['address'];
        }

        if($_POST['birthday_month'] == 0){
          $month_error = "Please select month.";
        }else{
          $month = $_POST['birthday_month'];
        }

        if($_POST['day'] == 0){
          $day_error = "Please select day";
        }else{
          $day = $_POST['day'];
        }

        if($_POST['year'] == 0){
          $year_error = "Please select year";
        }else{
          $year = $_POST['year'];
        }

        if($_POST['gender'] == 0){
          $gender_error = "Please select gender";
        }else{
          $gender = $_POST['gender'];
        }

        if($_POST['course'] == 0){
          $course_error = "Please select course.";
        }else{
          $course = $_POST['course'];
        }

        if(empty($_POST['yr_sec'])){
          $yr_sec_error = "Please input yr and sec";
        }else{
          $yr_sec = $_POST['yr_sec'];
        }

        if(empty($_POST['checkbox'])){
          $checkbox_error = "Required";
        }else{

        }

        if($id!="" && $username!="" && $password!="" && $firstname!="" && $lastname!="" && $email!="" && $address!="" && $month!="" && $day!="" && $year!="" && $gender!="" && $course!="" && $yr_sec!="" && $checkbox_error!="" ){
          require("session/DBConnection.php");
          $sql_insert = "INSERT INTO members(id_no, username, password, firstname, lastname, email, address,  gender, course, yr_sec)
                        VALUES('$id', '$username', '$password', '$firstname', '$lastname', '$email', '$address', '$gender', '$course', '$yr_sec')";
          mysql_query($sql_insert);

        }
    }

    ?>