PHP Post参数传递验证当值为空时

Question

在发布服务器端验证的选择值时遇到问题。当用户没有做出选择时，仍然在“选择...”上选择它。它仍然传递empty()方法，尽管该值为空。

<?php

// Email Properties
$email_to = "[email protected]";
$email_subject = "3DMark3t Contact:";
$first_name = $_POST['first_name'];
$last_name = $_POST['last_name'];
$email = $_POST['email'];
$telephone = $_POST['telephone'];
$comments = $_POST['comments'];
$select = $_POST['select'];

function formError($error) {
    // your error code can go here
    echo "We are very sorry, but there were error(s) found with the form you submitted. ";
    echo "These errors appear below.<br /><br />";
    echo $error."<br /><br />";
    echo "Please go back and fix these errors.<br /><br />";
    die();
}

// Make sure all fields are not empty
if(empty($first_name) || empty($last_name) || empty($email) ||
    empty(telephone) || empty($comments) || empty($select)) {
    // Return error
    formError('Please fill in all of the fields.');       
}

// Regex Tests
$error_message = "";

// Expressions
$email_exp = '/^[A-Za-z0-9._%-]+@[A-Za-z0-9.-]+\.[A-Za-z]{2,4}$/';
$string_exp = "/^[A-Za-z .'-]+$/";

if(!preg_match($email_exp, $email_from)) {
    $error_message .= 'The Email Address you entered does not appear to be valid.<br />';
}
if(!preg_match($string_exp, $first_name)) {
    $error_message .= 'The First Name you entered does not appear to be valid.<br />';
}
if(!preg_match($string_exp, $last_name)) {
    $error_message .= 'The Last Name you entered does not appear to be valid.<br />';
}
if(!empty($error_message)) {
    formError($error_message);
}

$email_message = "3DMark3t Contact: \n";
$email_message .= "First Name: {$first_name} \n";
$email_message .= "Last Name: {$last_name} \n";
$email_message .= "Email: {$email} \n";
$email_message .= "Telephone: {$telephone} \n";
$email_message .= "Select One: {$select} \n";
$email_message .= "Comments: {$comments} \n";

// Create email headers
$headers = 'From: '.$email_from."\r\n".
'Reply-To: '.$email_from."\r\n" .
'X-Mailer: PHP/' . phpversion();
@mail($email_to, $email_subject, $email_message, $headers);  

header("Location /");

HTML：

<form name="htmlform" method="post" action="php/html_form_send.php">
    <table width="450px">
        <tr>
            <td valign="top">
                <label for="first_name">First Name *</label>
            </td>
            <td valign="top">
                <input  type="text" name="first_name" maxlength="30" size="30">
            </td>
        </tr>
        <tr>
            <td valign="top">
                <label for="last_name">Last Name *</label>
            </td>
            <td valign="top">
                <input  type="text" name="last_name" maxlength="30" size="30">
            </td>
        </tr>
        <tr>
            <td valign="top">
                <label for="email">Email Address *</label>
            </td>
            <td valign="top">
                <input  type="text" name="email" maxlength="30" size="30">
            </td>
        </tr>
        <tr>
            <td valign="top">
                <label for="telephone">Telephone Number</label>
            </td>
            <td valign="top">
                <input  type="text" name="telephone" maxlength="30" size="30">
            </td>
        </tr>
        <tr>
            <td valign="top">
                <label for="select">Select One *</label>
            </td>
            <td valign="top">
                <select name="select">
                    <option value="">Select...</option>
                    <option value="3DModels">3DModels</option>
                    <option value="Graphic Design">Graphic Design</option>
                    <option value="Web Design">Web Design</option>
                    <option value="Tutorials">Tutorials</option>
                    <option value="Report">Report</option>
                    <option value="Requests">Requests</option>
                </select>
            </td>
        </tr>
        <tr>
            <td valign="top">
                <label for="comments">Comments *</label>
            </td>
            <td valign="top">
                <textarea  name="comments" maxlength="1000" cols="32.5" rows="6"></textarea>
            </td>
        </tr>
        <tr>
            <td colspan="2" style="text-align:center">
             <input type="submit" value="Submit">
            </td>
        </tr>
    </table>
</form>

Answer 1

您正在测试是否设置了 $_POST['formGender']，但对于空字符串上的 isset()，PHP 将返回 TRUE。表单上没有选择意味着 $_POST['formGender'] == ""，并且在 isset() 检查中被视为“设置”。

相反，测试它是否是 empty()都会验证变量是否像 isset() 一样定义以及它是否具有非空值。

if(empty($_POST['formGender']))
{
  $errorMessage .= "<li>You forgot to select your Gender!</li>";
}

还要在这里测试 empty() 而不是 !isset()

 if(!isset($_POST['first_name']) ||
    !isset($_POST['last_name']) ||
    !isset($_POST['email']) ||
    !isset($_POST['telephone']) ||
    !isset($_POST['comments'])) {
 if(empty($_POST['select']) )

Update

我不太确定你想用这个来完成什么。但是，3DModels、图形设计等不会成为$_POST数组的一部分。它们是 $_POST['select'] 的潜在值。我不明白你在这里的意图是什么。

if(empty($_POST['select']) )
{
  $var3dmodels = $_POST['3DModels'];
  $vargraphic_design = $_POST['Graphic Design'];
  $varweb_design = $_POST['Web Design'];
  $vartutorials = $_POST['Tutorials'];
  $varreport = $_POST['Report'];
  $varrequests = $_POST['Requests'];
}

你的问题根源：

我终于明白你的错误在哪里了。您正在为 $_POST['select'] 使用 $errorMessage，而不是 $error_message：

if(empty($_POST['select']))
{
  // Oops...
  $errorMessage .= 'The selection you made does not appear to be valid.<br />';

  // Should be
  $error_message .= 'The selection you made does not appear to be valid.<br />';
}

您应该启用 error_reporting PHP.ini 中的 code> 和 display_errors 仅用于开发和测试。使用像 $errorMessage .= ... 这样的未初始化变量会发出注意，你会看到屏幕上的错误。对于生产代码，请关闭此功能。

// Report all errors and notices
error_reporting(E_ALL);
ini_set('display_errors', 1);

Answer 2

试试这个：

   if(!isset($_POST['first_name']) ||
    !isset($_POST['last_name']) ||
    !isset($_POST['email']) ||
    !isset($_POST['telephone']) ||
    !isset($_POST['comments'])) ||
     $_POST['formGender'] == '')

Answer 3

使用 javascript/jquery 评估输入字段的值怎么样？然后，如果未填写所需的输入字段，您将能够在提交时返回 false。