使用$ _POST验证html / PHP字段中的重复条目

Question

paper_add.php is an html form to post values to another php page named paper_entry.php.

I would like to use validation for not allowing duplicate entries to go in database instead it would give them error message that some of the values are duplicate.

I tried comparing string but it only works if there are 2 variable, i also tried using in_array() but that didn't work. I am posting both pages so that if anyone could point me in the right direction, i would be really happy and continue my project.

I want to ensure that q1q1 is not the same as q1q2 and so on before i allow it to be inserted into the database

<?php include 'header.php'; ?>
<div class="container">
    <table class="table table-bordered">
        <thead>
            <tr>
                <th colspan='2'><u>Add Paper</u></th>
            </tr>
        </thead>
        <tbody>
            <form method="post" action="paper_entry.php">
            <tr>
                <td>Examination </td>
                <td><input type="text" required="required" class="form-control"   name="examination"></td>
            </tr>
            <tr>
                <td>Subject </td>
                <td><input type="text" required="required" class="form-control"   name="subject"></td>
            </tr>
            <tr>
                <td>Subject Code </td>
                <td><input type="text" required="required" class="form-control"  name="subject_code"></td>
            </tr>
            <tr>
                <td>Category</td>
                <td><input type="text" required="required" class="form-control"  name="category"></td>
            </tr>
            <tr>
                <td>Month & Year:</td>
                <td><input type="text" required="required" class="form-control"  name="month_year"></td>
            </tr>
            <input type="hidden" required="required" class="form-control"  name="created_by" value="<?php echo $_SESSION ['user'] ?>">
            <tr>
                <td>Question 1 (1) :</td>
                <td><input type="text" required="required" class="form-control"  name="q1q1"></td>
            </tr>
            <tr>
                <td>Question 1 (2) :</td>
                <td><input type="text" required="required" class="form-control"  name="q1q2"></td>
            </tr>
            <tr>
                <td>Question 1 (3) :</td>
                <td><input type="text" required="required" class="form-control"  name="q1q3"></td>
            </tr>
            <tr>
                <td>Question 1 (4) :</td>
                <td><input type="text" required="required" class="form-control"  name="q1q4"></td>
            </tr>
            <tr>
                <td>Question 1 (5) :</td>
                <td><input type="text" required="required" class="form-control"  name="q1q5"></td>
            </tr>
            <tr>
                <td>Question 1 (6) :</td>
                <td><input type="text" required="required" class="form-control"  name="q1q6"></td>
            </tr>
            <tr>
                <td>Question 1 (7) :</td>
                <td><input type="text" required="required" class="form-control"  name="q1q7"></td>
            </tr>
            <tr>
                <td>Question 1 (8) :</td>
                <td><input type="text" required="required" class="form-control"  name="q1q8"></td>
            </tr>
            <tr>
                <td>Question 2 (A) :</td>
                <td><input type="text" required="required" class="form-control"  name="q2qa"></td>
            </tr>
            <tr>
                <td>Question 2 (B) :</td>
                <td><input type="text" required="required" class="form-control"  name="q2qb"></td>
            </tr>
            <tr>
                <td>Question 2 (Or A) :</td>
                <td><input type="text" required="required" class="form-control"  name="q2qoa"></td>
            </tr>
            <tr>
                <td>Question 2 (Or B) :</td>
                <td><input type="text" required="required" class="form-control"  name="q2qob"></td>
            </tr>
            <tr>
                <td>Question 3 (A) :</td>
                <td><input type="text" required="required" class="form-control"  name="q3qa"></td>
            </tr>
            <tr>
                <td>Question 3 (B) :</td>
                <td><input type="text" required="required" class="form-control"  name="q3qb"></td>
            </tr>
            <tr>
                <td>Question 3 (Or B) :</td>
                <td><input type="text" required="required" class="form-control"  name="q3qob"></td>
            </tr>
            <tr>
                <td>Question 4 (A) :</td>
                <td><input type="text" required="required" class="form-control"  name="q4qa"></td>
            </tr>
            <tr>
                <td>Question 4 (B) :</td>
                <td><input type="text" required="required" class="form-control"  name="q4qb"></td>
            </tr>
            <tr>
                <td>Question 5 (1) :</td>
                <td><input type="text" required="required" class="form-control"  name="q5q1"></td>
            </tr>
            <tr>
                <td>Question 5 (2) :</td>
                <td><input type="text" required="required" class="form-control"  name="q5q2"></td>
            </tr>
            <tr>
                <td>Question 5 (3) :</td>
                <td><input type="text" required="required" class="form-control"  name="q5q3"></td>
            </tr>
            <tr>
                <td>Submit : </td>
                <td><input type="submit" name="submit"></td>
            </tr>
        </tbody>
    </table>
</div>

paper_entry.php

<?php
include 'header1.php';
$examination  = $_POST["examination"];
$subject      = $_POST["subject"];
$subject_code = $_POST["subject_code"];
$category     = $_POST["category"];
$month_year   = $_POST["month_year"];
$created_by   = $_POST["created_by"];

$q1q1  = $_POST["q1q1"];
$q1q2  = $_POST["q1q2"];
$q1q3  = $_POST["q1q3"];
$q1q4  = $_POST["q1q4"];
$q1q5  = $_POST["q1q5"];
$q1q6  = $_POST["q1q6"];
$q1q7  = $_POST["q1q7"];
$q1q8  = $_POST["q1q8"];
$q2qa  = $_POST["q2qa"];
$q2qb  = $_POST["q2qb"];
$q2qoa = $_POST["q2qoa"];
$q2qob = $_POST["q2qob"];
$q3qa  = $_POST["q3qa"];
$q3qb  = $_POST["q3qb"];
$q3qob = $_POST["q3qob"];
$q4qa  = $_POST["q4qa"];
$q4qb  = $_POST["q4qb"];
$q5q1  = $_POST["q5q1"];
$q5q2  = $_POST["q5q2"];
$q5q3  = $_POST["q5q3"];

include 'dbconnect.php';

$sql = "INSERT INTO paper (id , examination, subject,subject_code,category,month_year,created_by,q1q1,q1q2,q1q3,q1q4,q1q5,q1q6,q1q7,q1q8,q2qa,q2qb,q2qoa,q2qob,q3qa,q3qb,q3qob,q4qa,q4qb,q5q1,q5q2,q5q3)
          VALUES ('','$examination','$subject','$subject_code','$category','$month_year','$created_by','$q1q1','$q1q2','$q1q3','$q1q4','$q1q5','$q1q6','$q1q7','$q1q8','$q2qa','$q2qb','$q2qoa','$q2qob','$q3qa','$q3qb','$q3qob','$q4qa','$q4qb','$q5q1','$q5q2','$q5q3')";

if (mysqli_query($conn, $sql)) {
    echo "<center> <h2><a href='paper_list.php'> Paper Added, Click Here For List. </h2> </center></a>";
} else {
    echo "Error: " . $sql . "<br>" . mysqli_error($conn);
}

include 'footer.php';
?>

Answer 1

You could do something like:

$post_array = [
        'q1q1' => 'test ', 
        'q1q2' => 'testing', 
        'q1q3' => 'test', 
        'q2qa' => 'tester', 
        'q2qoa' => 'test2', 
        'q3qob' => 'tests'
    ];

$keys = array_keys($post_array);

foreach ($keys as $key) {
    foreach ($post_array as $k => $v) {
        if ($key != $k) {
            if (trim(strtolower($v)) == trim(strtolower($post_array[$key]))) {
                echo "The value '{$v}' in {$key} matches the value in {$k}<br />";
            }
        } else {
            continue;
        }
    }
}

I have a gut feeling array_reduce would work better, but this should work, you'd need to modify it to suit your post array, I've just added default values here as an example. You could also do a similar approach with Javascript to do it client side.

All it does is loop the keys of your post array and then checks the values of the other items skipping the item it's comparing against. It means you'll get a result for each duplicate, but I assume you'll want to add a warning on all matches?

Anyway, hope it helps to get you closer to a solution.