How to save a PHP variable when a page loads twice - php

Question

A user enters two dates periods on a text-box and a SQL select statement picks mobile numbers from a database entered in between the period. I want to pick and display them on a page. On the same display page, I have a text area where a user can type a message and on submit, it should be sent to these selected numbers and displayed mobile numbers. I am having a challenge on passing the $mobilenumber to the function sendbulk that is to send the message to the mobile numbers displayed by $mobilenumber variable. Everything else is okay apart from passing the $mobilenumber. I think this is because after the page loads to display the contacts selected, on the second load as you submit the $message to bulk function the value of $mobilenumber is already lost. How can I save it.
Check sample code below and please advice. How do I save the $mobilenumber so that by the second load it is still there to be passed to the function sendbulk()? Anyone?
<?php
//Define variable and set to empty values
$message = "";
if ($_SERVER["REQUEST_METHOD"] == "POST") {
$message = test_input($_POST['message']);
echo "$message";
}
function test_input($data) {
$data = trim($data);
$data = stripslashes($data);
$data = htmlspecialchars($data);
return $data;
}
$time1 = isset($_POST['t1']) ? $_POST['t1'] : 'default something missing';
$time2 = isset($_POST['t2']) ? $_POST['t2'] : 'default something missing';
//connection
$sql = "SELECT DISTINCT msisdn FROM customer WHERE DATE_FORMAT(time_paid, '%Y-%c-%e') BETWEEN ADDDATE('$time1',INTERVAL 0 HOUR) AND ADDDATE('$time2',INTERVAL '23:59' HOUR_MINUTE)";
$result = $conn->query($sql);
if ($result->num_rows > 0) {
echo " Recipients: "; echo "$result->num_rows <br> <br>";
// output data of each row
while($row = $result->fetch_assoc()) {
$mobilenumber = $row['msisdn'];
echo "Mobile : " . "$mobilenumber" . "<br>";
}
} else {
echo "No Contacts to Display";
}
$conn->close();
sendbulk($mobilenumber,$message);
?>
<center></center> <form method="post" action="<?php echo htmlspecialchars($_SERVER["PHP_SELF"]);?>">
<textarea name='message' rows="6" cols="60" placeholder="Please Type Your Message Here"></textarea>
<br><br>
<input type="submit" name="submit" value="Send Message">
</form></center>
<?php
function sendbulk($mobilenumber,$message) {
echo "$mobilenumber";
echo "$message";
$serviceArguments = array(
"mobilenumber" => $mobilenumber,
"message" => $message_sent
);
$client = new SoapClient("http://*******");
$result = $client->process($serviceArguments);
return $result;
}

Answer 1

You use sessions.
Here is a sample code:
<?php
session_start();
if (!isset($_SESSION['count'])) {
$_SESSION['count'] = 0;
} else {
$_SESSION['count'] += 1;
}
echo $_SESSION['count'];
?>
Keep reloading this file via your web server. You should see the variable incrementing.
As an alternative, you can also use $_COOKIE. The only difference is that $_SESSION is saved on the server side and not accessible on the client. To identify the client it does store a cookie for that session on the client.
$_COOKIE on the other hand is completely stored on the client and passed by the browsers to the server on every request.
Also note a caveat, don't overload your session variables or cookies as it will hit your response times.
Also note that session_start() is required in every PHP file where you want to access the session.