使用数据库中的值检查变量值

Question

I have been trying to work this out for 2 days now without success. I am trying to check form input values against existing values in a column called 'date' in the 'bookings' table in the database. If any matches are found, then the whole result needs to be false so that the query wont run.

My code is such a mess of attempts, but I'm now showing the only idea that half worked. A user chooses a date or a date range. These dates are checked against what exists in the 'date' column in the database. If any of the dates exist, the whole thing needs to be false, if none of the dates are found, it must be true and then those values can be saved to the database. Here is what I have:

    $sql = "
SELECT date
FROM bookings
;";

$result = $conn->query($sql);
$alreadyBooked = array();

if ($result->num_rows > 0) {
    // output data of each row
    while($row = $result->fetch_assoc()) {
        $alreadyBooked[] = $row['date'];
    } // while
} //  num rows


if(isset($_POST['submit'])){

$name = $_POST['name'];
$email = $_POST['email'];
$tel = $_POST['tel'];
$arrive = strtotime($_POST['arrive']);
$depart = (strtotime($_POST['depart'])) - 86400;
?>

<p>You have chosen the following dates: </p>
 <a name="booking-form"></a> 

<?php



for ( $i = $arrive; $i <= $depart; $i = $i + 86400 ) {
        echo $bookedDates = date('Y-m-d', $i );


        if (in_array($bookedDates, $alreadyBooked)){
            $bookdedDatesNice = date('D, j M Y', strtotime($bookedDates));
            echo 'This date is not available : '.$bookdedDatesNice.'<br />';

        } else {

            echo 'Your dates are available';

            $sqlinsert = "INSERT INTO bookings (name, email, tel, roomid, date) values ";
            // Loop between timestamps, 24 hours at a time
                for ( $i = $arrive; $i <= $depart; $i = $i + 86400 ) {
                    $bookedDates =date('Y-m-d', $i ); 
                    // Constructing the insert query
                 $sqlinsert .= " ('$name', '$email', '$tel', '$roomId', '$bookedDates'),";
            }

            $bulk_insert_query = rtrim($sqlinsert, ","); // to remove last comma
            $resultinsert = $conn->query($bulk_insert_query); 
            ?>


            <p>Your booking has been received for: <br />
            Please wait for a confirmation email on: <?php echo $email; ?>

            </p>



        <?php
        // header('refresh:3; url=book.php?id='.$id.'#booking-form');

        }// if  
}   // for

}

Please can someone help out by showing me an example code of how to solve this issue. I am still a newbie at PHP.

Answer 1

Make an SQL request, fill the response into an array (which you already do), make a function that takes an array as an argument.

function checkDate($dates){ //dates is the array you get from your SQL
   foreach($dates as $date){
     if($_POST['date'] == $date){
     return false;
     }
   }
return true;
}

If you get true out of this function you can enter that date into your database, if it is false then you already have that date booked.

Answer 2

I don't know how to change the insert code to a prepared statement, because I found this bulk insert code off the internet, and honestly don't know how to convert it to a prepared statement.

I have managed to figure it out:

<?php
            $sql = "
            SELECT date
            FROM bookings
            WHERE roomid = $roomId;
            ;";

            $result = $conn->query($sql);
            $alreadyBooked = array();

            if ($result->num_rows > 0) {
                // output data of each row
                while($row = $result->fetch_assoc()) {
                    $alreadyBooked[] = $row['date'];
                } // while
            } //  num rows






            if(isset($_POST['submit'])){

                $name = $_POST['name'];
                $email = $_POST['email'];
                $tel = $_POST['tel'];
                $arrive = strtotime($_POST['arrive']);
                $depart = (strtotime($_POST['depart'])) - 86400;
                ?>

                <a name="booking-form"></a> 
                <h2>Viewing <?php echo $roomname; ?></h2>
                <h3>You have chosen the following dates: </h3>



                <?php
                // show which dates the user chose
                for ( $i = $arrive; $i <= $depart; $i = $i + 86400 ) {
                        echo $bookedDatesecho = date('D, j M Y', $i ).'<br />';
                 }

                // save the dates the user chose into an array
                for ( $i = $arrive; $i <= $depart; $i = $i + 86400 ) {
                    $bookedDates[] = date('Y-m-d', $i );
                }                   

                // checking dates chosen from form with dates in the database
                $compareDateResult = array_intersect($alreadyBooked,$bookedDates);

                // if statement to check whether the dates chosen are available or not and then do something
                if (empty($compareDateResult)){

                    // save booking to the database
                    $sqlinsert = "INSERT INTO bookings (name, email, tel, roomid, date) values ";
                    // Loop between timestamps, 24 hours at a time
                        for ( $i = $arrive; $i <= $depart; $i = $i + 86400 ) {
                            $bookedDates =date('Y-m-d', $i ); 
                            // Constructing the insert query
                         $sqlinsert .= " ('$name', '$email', '$tel', '$roomId', '$bookedDates'),";
                    }

                    $bulk_insert_query = rtrim($sqlinsert, ","); // to remove last comma
                    $resultinsert = $conn->query($bulk_insert_query);   
                    ?>
                    <p>Your booking has been received for: <br />
                    Please wait for a confirmation email on: <?php echo $email; ?></p>

                <?php 
                } else { ?>

                    <h3>These dates are not available:</h3>


                    <?php 
                    foreach ($compareDateResult as $value) {
                        //echo 'the date: '.$value.' <br />';
                        $value2 = strtotime($value);
                        echo date('D, j M Y',$value2).'<br />'; 
                    } // foreach
                    ?>
                    <p><a href="book.php?id=<?php echo $id; ?>">Please try again</a></p>

                <?php   
                } // if                 




             } else {  ?>



                <h2>Booking Form</h2>       
                <form id="booking-form" method="post" action="#booking-form" />

                    <input type="hidden" name="<?php echo $roomId; ?>" />

                    <label>Name</label><br />
                    <input type="text" name="name" required />
                    <div class="clear20"></div>

                    <label>Email</label><br />
                    <input type="email" name="email" required/>
                    <div class="clear20"></div>

                    <label>Telephone</label><br />
                    <input type="text" name="tel" required />
                    <div class="clear20"></div>

                    <label>Arrive on: </label>
                    <input type="date" name="arrive" required/> at 2pm
                    <div class="clear20"></div>

                    <label>Depart on: </label>
                    <input type="date" name="depart" required/> at noon
                    <div class="clear20"></div>

                    <input type="submit" name="submit" value="Book &raquo;"/>

                </form>

            <?php }     ?>