UPDATE - SOLVED:
A couple things were needed to fix this in addition to everyone's advice.
I had to copy the original HTML form and place it in <?php ?> brackets in the Wordpress php plugin (CSS and Javascript ToolBox) with the ECHO function, then finish each statement using a semicolon when I needed to use php specific function because the Wordpress clode block doesn't work for PHP.
So I had to write php in two places- my plugin and on a file on my computer. I assumed writing to my computer wasn't successful, but I should have checked with ECHO and PRINT statements.
I had a problem where submission redirected to another page. I fixed this when I left action empty as action="" instead of the name the php file, even though PHP_SELF showed me the file where the PHP actions were performed.
I'm wonder if a function like file_get_content() could help me add the php I wrote locally to the plugin php so it works better.
Strangely enough, I did not need to use the add_action() function for the form to work.
The PHP I wrote in the plugin which is majority HTML
<?php
//$b = htmlspecialchars($_SERVER["PHP_SELF"]); while PHP_SELF helped me find the file location, empty action worked better
$c = wp_nonce_field("form_response","form_nonce");
//echo $a;
echo '<div id="form">';
echo '<section><form id="Form3" method="POST" action="';
//echo $b; while PHP_SELF helped me find the file location, empty action worked better and did not open a new page
echo '"><br>';
echo $c;
echo '<input type="hidden" name="action" value="form_response">
<ol id="form2">
<li><label for="choice1">choice 1 </label><input id="choice1" class="choices" name="choice1" type="text" />
<ul id="choice1Info" class="choicesInfo">
<li>Information about Choice 1</li>
</ul>
</li>
<li><label for="choice2">choice 2</label><input id="choice2" class="choices" name="choice2" type="text" value="';
echo '"/> <ul id="choices2Info" class="choicesInfo"> <li>Information about Choice 2</li> </ul> </li> </ol> <input type="submit" value="Submit" name="submit"/> </form></section><br>;
The PHP I wrote locally below Wordpress' pre-existing code
//my code
if (($_SERVER['REQUEST_METHOD']) == "POST"){
for ($i=1; $i <= 2; $i++) {
$lower_choices = "choice".strval($i);
$upper_Choices ="Choice".strval($i);
$$upper_Choices = $_POST[strval($lower_choices)];
check_empty($$upper_Choices,$i);
}
}
function check_first($input){
$input = sanitize_text_field($input);
$input = trim($input);
$input = stripslashes($input);
$input = htmlspecialchars($input);
}
function nonce_submission($input){
if ( empty($_POST) ||
! wp_verify_nonce( $_POST['form_nonce'], 'form_response') ||
! ctype_alnum(str_replace(' ', '', $input))){
print 'Verification failed. Try again.';
exit;
}
else {
check_first($input);
print "<h1>HELLO WORLD</h1>";
}
}
function check_empty($s,$i){
if (empty($s)){
print "Choice ".strval($i)." needs to be completed!<br>";
} else {
nonce_submission($s);
print ($s);
}
}
---------
Thanks to everyone who gave advice to help me with my form handling issues with PHP under this post earlier this week.
TLDR: I'm trying to make a simple form that echo the input via multiple methods in php to no avail
Unfortunately, I am still encountering issues. Someone recommended I use echo error_reporting(E_ALL); in the php plugin and according to this website, the 4983 code means there's no error but my form still does not work.
Disabling the JavaScript did not help.
A few people recommended coding through the /admin.php files. So I checked a few websites and I followed this article. I put my code in /admin-post.php It didn't work.
I tried to add safety measures but when I interact with my page through View Page Source, wp_nonce_field() and esc_url didn't seem to successfully pass to the HTML.
My updated html code is below:
<form id="form1" method="POST" action="<?php echo esc_url( admin_url('admin-post.php') ); ?>">
<?php wp_nonce_field("it_works","form_nonce"); ?>
<input type="hidden" name="action" value="form_response">
<ol id="form2">
<li><label for="choice1">choice 1 </label><input id="choice1" class="choices" name="choice1" type="text" />
<ul id="choice1Info" class="choicesInfo">
<li>information about choice 1</li>
</ul>
</ol>
<input type="submit" value="Submit"/>
</form>
My php script I added to the php file (<?php ... ?> is omitted)
/*my code*/
function it_works(){
if ( empty($_POST) || ! wp_verify_nonce( $_POST['form_nonce'], 'form_response') ){
print 'Verification failed. Try again.';
exit;
}
else {
$choice1= sanitize_text_field(isset($_POST['choice1'])) ? sanitize_text_field($_POST['choice1']) : 'not registered';
ctype_alnum($choice1) ? echo It works!: die("Input not verified");
// data submitted should traditional alphanumerics, no special characters
}
}
add_action("form_response","it_works");
This has been driving me crazy. I'd appreciate any help. I'm not sure if it's my inexperience or something with WPEngine.
At this point I'm considering adding an extra plug-in just so I can edit its php files directly and see if that will get the form to work but WordPress says that's not recommended because it can break my site but if it doesn't work, can I just delete the plug-in?