Submitting contact form data - php

Question

The contact form has several text fields and several dropdowns with the ability to select multiple values. The question is how to send these values by e-mail? Text values of type string (one word at a time) are sent fine. But how to send arrays containing multiple values? How to collect them using the $_POST method and put them in a letter?
Form:
<section class="post-content-area pt-20">
<div class="container">
<div class="row">
<div class="col-lg-8 posts-list">
<div class="card card-signin my-5">
<div class="card-body">
<h5 class="card-title text-center" style="font-size: 26px">Test contact form</h5>
<form method="post" action="email-script.php" enctype="multipart/form-data" id="emailForm">
<div class="form-group">
<input type="text" name="name" id="name" class="form-control" placeholder="Name" >
<div id="nameError" style="color: red;font-size: 14px;display: none">nameError</div>
</div>
<div class="form-group">
<input type="text" name="surname" id="surname" class="form-control" placeholder="Surame" >
<div id="nameError" style="color: red;font-size: 14px;display: none">nameError</div>
</div>
<div class="form-group">
<input type="text" name="phone" id="phone" class="form-control" placeholder="Phone" >
<div id="subjectError" style="color: red;font-size: 14px;display: none">subjectError</div>
</div>
<div class="form-group">
<label>First Level Category</label><br />
<select id="first_level" name="first_level[]" multiple class="form-control">
<?php
foreach($result as $row)
{
echo '<option value="'.$row["first_level_category_id"].'">'.$row["first_level_category_name"].'</option>';
}
?>
</select>
</div>
<div class="form-group">
<label>Second Level Category</label><br />
<select id="second_level" name="second_level[]" multiple class="form-control">
</select>
</div>
<div class="form-group">
<label>Third Level Category</label><br />
<select id="third_level" name="third_level[]" multiple class="form-control">
</select>
</div>
<div class="form-group">
<input type="file" name="attachment" id="attachment" class="form-control">
<div id="attachmentError" style="color: red;font-size: 14px;display: none">attachmentError</div>
</div>
<div class="submit">
<center><input type="submit" name="submit" onclick="return validateEmailSendForm();" class="btn btn-success" value="SUBMIT"></center>
</div>
</form>
</div>
</div>
</div>
</div>
</div>
</section>
Emailing script:
https://pastebin.com/3SR67MUP

Answer 1

There are multiple ways on how to send them via email.
The easiest way is getting them on your form action page and sending them with the php mail() function.
To make the email look better you can create an HTML email template file.
Then get the file data with file_get_contents() and resetting strings with your collected data with the str_replace function and putting the data into your mail funtion.
Hope it helps!