提交后保留字段值


Retain field values after submit

我需要此表单的操作来调用我的脚本,然后如果电子邮件地址已经在数据库中,它应该显示警报。

这很有效,但很明显,我被引导到空白的脚本页面,当我返回表单时,数据就不见了。

我希望重定向到数据完整的表单并显示警报。

我一整天都在努力让会议开始工作,现在我只是感到困惑。

如果有人能告诉我在哪里添加每个页面的会话代码,我会非常感激

这个页面包含我的表单:

<!doctype html>
<html>
<head>
    <meta charset="utf-8">
    <title>Untitled Document</title>
    <script src='http://ajax.googleapis.com/ajax/libs/jquery/1.6.2/jquery.min.js'></script>
    <script src='http://ajax.microsoft.com/ajax/jquery.validate/1.7/additional-methods.js'></script>
    <script src='http://ajax.aspnetcdn.com/ajax/jquery.validate/1.11.1/jquery.validate.js'></script>
    <script src="../js/register_validate.js" type="text/javascript"></script>
    <link href="../css/styles.css" rel="stylesheet" type="text/css">
    <base target="_top">
</head>
<body>
    <p><?php include ('register_form2.php') ?></p>                    
</body>
</html>

这是包含的表单页面:

<form action="register_script2.php" method="POST" name="form_register" id="form_registerID" accept-charset="UTF-8">
    <aside class="field_reg_form">
    <input name="field_email1" type="text" required id="field_email1ID" /><br /><br />
    <input name="field_email2" type="text" required id="field_email2ID" /><br /><br />
    <input type="submit" value="submit" id="submit" name="submit" />
    </aside>

</form>

以下是PHP脚本:

<?php
require_once('../scripts/connect.php');
$con = mysqli_connect(DBHOST, DBUSER, DBPASS, DBNAME) or die('Could not connect to database server.');
if(isset($_POST['submit'])) {
    $var_Email1 = mysqli_real_escape_string($con, $_POST['field_email1']);
    $var_Email2 = mysqli_real_escape_string($con, $_POST['field_email2']);
        if ($var_Email1 == $var_Email2){
            $sql = mysqli_query($con, "SELECT * FROM membership WHERE Email = '$var_Email1' "); 
                if(mysqli_num_rows($sql) > 0 ){
                    print '<script type="text/javascript">'; 
                    print 'alert("The email address '. $_POST['field_email1'].' is already in our database")'; 
                    print '</script>'; 
                      exit();
                }
        echo "not in database";
   }
}
?>

是的,在这种情况下,您可以实现(某种)闪存会话:

因此,在提交时:

<?php
session_start(); // don't forget
require_once('../scripts/connect.php');
$con = mysqli_connect(DBHOST, DBUSER, DBPASS, DBNAME) or die('Could not connect to database server.');
if(isset($_POST['submit'])) {
    $var_Email1 = mysqli_real_escape_string($con, $_POST['field_email1']);
    $var_Email2 = mysqli_real_escape_string($con, $_POST['field_email2']);
    if ($var_Email1 == $var_Email2){
        $sql = mysqli_query($con, "SELECT * FROM membership WHERE Email = '$var_Email1' "); 
        if(mysqli_num_rows($sql) > 0){
            // set session
            $_SESSION['email_exists'] = $var_Email1;
            header('Location: the_starting_php.php');
            exit;
        }
    }
    echo "not in database";
}
?>

然后在表单页面中添加以下内容:

<?php
session_start();
// check if there is
$email = '';
if(isset($_SESSION['email_exists'])) {
    $email = $_SESSION['email_exists'];
    unset($_SESSION['email_exists']); // unset it
    echo "
      <script type='text/javascript'>
      alert('The email address $email already exists');
      </script>
    ";
}
?>

<form action="register_script2.php" method="POST" name="form_register" id="form_registerID" accept-charset="UTF-8">
    <aside class="field_reg_form">
          <input name="field_email1" type="text" required id="field_email1ID" value="<?php echo $email; ?>" />
          <br /><br />
          <input name="field_email2" type="text" required id="field_email2ID" value="<?php echo $email; ?>" />
          <br /><br />
          <input type="submit" value="submit" id="submit" name="submit" />
    </aside>
</form>

旁注:我建议使用事先准备好的陈述。

<?php
session_start(); // don't forget
require_once('../scripts/connect.php');
$con = mysqli_connect(DBHOST, DBUSER, DBPASS, DBNAME) or die('Could not connect to database server.');
if(isset($_POST['submit'])) {
    $var_Email1 = $_POST['field_email1'];
    $var_Email2 = $_POST['field_email2'];
    if ($var_Email1 == $var_Email2){
        $sql = 'SELECT * FROM membership WHERE Email = ?'; 
        $select = $con->prepare($sql);
        $select->bind_param('s', $var_Email1);
        $select->execute();
        if($select->num_rows > 0){
            // set session
            $_SESSION['email_exists'] = $var_Email1;
            header('Location: the_starting_php.php');
            exit;
        }
    }
    echo "not in database";
}
?>

我知道你发布了代码,但我仍然是;不确定工作流。然而,我会给你一个"例如",看看你是否至少能坚持这个想法。

给定您的表单,还提供value属性并从$_POST值中提取它们:

register_form.php

<!-- keeping it brief... -->
<form method="POST">
  <input type="email" name="email1" value="<?= $_POST['email1']; ?>" />
  <input type="email" name="email2" value="<?= $_POST['email2']; ?>" />
  <input type="submit" value />
</form>

然后根据原始请求输出:

<!-- ... -->
<?php include('register_form.php'); ?>
<!-- ... -->

然后,在您提交的页面中也调用它(这次它将由传入值预先填充):

<!-- ... -->
<?php if (isset($_POST['submit'])) { ... } ?>
<!-- ... -->
<?php include('register_form.php'); ?>
<!-- ... -->

您可以使用ajax发送数据,然后显示php脚本的返回,如下所示:

$.ajax({
    type: 'POST',
    url: 'register_script2.php',
    data: $('form#form_register').serialize()
})
.done(function(msg) {
      if(msg != 'error'){
          alert('The email address '+msg+' is already in our database');
      } else {
          // init your form
      }
});

在您的PHP代码中执行此操作;

...
if(mysqli_num_rows($sql) > 0 ){
    echo $var_Email1;
} else {
    echo 'error';
}
...