Stop PHP Execution But Display HTML - php

Question

In a Profile page of the User, I want to validate his input with PHP after submission and display errors on the same page before updating in the database.
For this, I'm doing something like:
<div>
<?php
if (isset($_POST["submitted"])) {
if (!isValidEmail($_POST["email"])) {
echo "<p>Please enter a valid email address.</p>";
return; // or exit;
}
if (!isValidPhoneNumber($_POST["phoneNumber"])) {
echo "<p>Please enter a valid phone number.</p>";
return; // or exit;
}
...
if (updateUser($id, $email, $phoneNumber, $name)) {
echo("<meta http-equiv='refresh' content='0'>");
} else {
echo "<p>An error occurred! Could not update your profile information!</p>";
}
}
?>
</div>
<my-footer></my-footer>
So when an error occurs upon PHP validation, the footer doesn't appear. So I understood that with return or exit the page will stop rendering at that command.
What can I do to solve this issue?
I want it to stop execution of the PHP script but display the rest of the HTML page.

Answer 1

You could put your validation logic inside a function at the top of your page, and change all your echo to return.
function validate() {
if (isset($_POST["submitted"])) {
if (!isValidEmail($_POST["email"])) {
return "<p>Please enter a valid email address.</p>";
}
if (!isValidPhoneNumber($_POST["phoneNumber"])) {
return "<p>Please enter a valid phone number.</p>";
}
//...
if (updateUser($id, $email, $phoneNumber, $name)) {
return "<meta http-equiv='refresh' content='0'>";
} else {
return "<p>An error occurred! Could not update your profile information!</p>";
}
}
}
Then simply echo the string returned from the function above the footer.
<div>
<?php echo validate(); ?>
</div>
<my-footer></my-footer>
Note that the above will work because $_POST is a superglobal. However, you may consider changing your function to pass email, phoneNumber, name and id as parameters instead.

Answer 2

Change your flow up a little bit...
if (isset($_POST["submitted"])) {
$has_errors = FALSE;
$err_msg = '';
if (!isValidEmail($_POST["email"])) {
$err_msg .= "<p>Please enter a valid email address.</p>";
$has_errors = TRUE;
}
if (!isValidPhoneNumber($_POST["phoneNumber"])) {
$err_msg .= "<p>Please enter a valid phone number.</p>";
$has_errors = TRUE;
}
if ( $has_errors ) {
echo "<p>Please Correct the following and resubmit...</p>" . $err_msg;
} else {
if (updateUser($id, $email, $phoneNumber, $name)) {
echo("<meta http-equiv='refresh' content='0'>");
} else {
echo "<p>An error occurred! Could not update your profile information!</p>";
}
}
}

Answer 3

Many times you will see PHP frameworks that can handle this for you.
Here's a good website to compare a few: http://phpframeworks.com/
But what you can do is put your footer (and / or the rest of your code) into a function that holds the rest of your code for you, and you can call it later or whenever you need to so you can still end code execution gracefully.
<div>
<?php
function footer() {
$string = "</div>";
$string .= "<my-footer></my-footer>";
return $string;
}
if (isset($_POST["submitted"])) {
if (!isValidEmail($_POST["email"])) {
echo "<p>Please enter a valid email address.</p>";
die(footer()); // Displays footer
}
if (!isValidPhoneNumber($_POST["phoneNumber"])) {
echo "<p>Please enter a valid phone number.</p>";
die(footer()); // Displays footer
}
...
if (updateUser($id, $email, $phoneNumber, $name)) {
echo("<meta http-equiv='refresh' content='0'>");
} else {
die("<p>An error occurred! Could not update your profile information!</p>" . footer()); // kills the page execution, but still returns the foot of the page.
}
}
echo footer();
?>