Handling Email Sending and Receiving with PHP: Text, HTML, and Attachments

In modern society, email is a key communication tool, and PHP provides functions to format and handle email content for readability and proper display.

1. Text Email Sending and Receiving

For simple plain‑text emails, the built‑in mail() function can be used; proper charset and MIME headers must be set. Example code shows setting $to, $subject, $message and $headers before calling mail().

$to = "[email protected]";
$subject = "Testing email";
$message = "This is a test email.";
$headers = "From: [email protected]<br/>";
$headers .= "MIME-Version: 1.0<br/>";
$headers .= "Content-Type: text/plain; charset=UTF-8<br/>";
mail($to, $subject, $message, $headers);

Receiving plain‑text emails can be done with the IMAP extension: imap_open() connects to the mailbox, imap_num_msg() gets the message count, and a loop with imap_header() and imap_fetchbody() retrieves each message.

$mailbox = imap_open("{mail.example.com:993/imap/ssl}INBOX", "username", "password");
$messageCount = imap_num_msg($mailbox);
for ($i = 1; $i <= $messageCount; $i++) {
    $header = imap_header($mailbox, $i);
    $subject = $header->subject;
    $fromAddress = $header->fromaddress;
    $message = imap_fetchbody($mailbox, $i, 1);
    // process email content
}
imap_close($mailbox);

2. HTML Email Sending and Receiving

When sending HTML content, libraries such as PHPMailer are recommended. The example configures SMTP, sets From/To, enables HTML, assigns an HTML body, and sends the message, handling errors via exceptions.

require 'vendor/autoload.php';
use PHPMailer\PHPMailer\PHPMailer;
use PHPMailer\PHPMailer\Exception;
$mail = new PHPMailer(true);
try {
    $mail->isSMTP();
    $mail->Host = 'smtp.example.com';
    $mail->SMTPAuth = true;
    $mail->Username = 'username';
    $mail->Password = 'password';
    $mail->SMTPSecure = 'tls';
    $mail->Port = 587;
    $mail->setFrom('[email protected]', 'Sender Name');
    $mail->addAddress('[email protected]', 'Recipient Name');
    $mail->Subject = 'Testing email';
    $mail->isHTML(true);
    $mail->Body = '<h1>This is a test email.</h1>';
    $mail->send();
    echo 'Email has been sent.';
} catch (Exception $e) {
    echo 'Email could not be sent. Error: ', $mail->ErrorInfo;
}

Receiving HTML mail also uses imap_fetchbody() with the part index for the HTML part.

$mailbox = imap_open("{mail.example.com:993/imap/ssl}INBOX", "username", "password");
$messageCount = imap_num_msg($mailbox);
for ($i = 1; $i <= $messageCount; $i++) {
    $header = imap_header($mailbox, $i);
    $subject = $header->subject;
    $fromAddress = $header->fromaddress;
    $message = imap_fetchbody($mailbox, $i, 2); // HTML part
    // process email content
}
imap_close($mailbox);

3. Attachment Handling

PHPMailer can add attachments with addAttachment(). Receiving attachments involves parsing the message structure with imap_fetchstructure(), iterating parts, detecting the filename parameter, fetching the body part, and saving it to a local file.

$mailbox = imap_open("{mail.example.com:993/imap/ssl}INBOX", "username", "password");
$messageCount = imap_num_msg($mailbox);
for ($i = 1; $i <= $messageCount; $i++) {
    $header = imap_header($mailbox, $i);
    $structure = imap_fetchstructure($mailbox, $i);
    foreach ($structure->parts as $partNum => $part) {
        if ($part->ifdparameters) {
            foreach ($part->dparameters as $param) {
                if (strtolower($param->attribute) == 'filename') {
                    $attachmentName = $param->value;
                    $attachmentData = imap_fetchbody($mailbox, $i, $partNum+1);
                    file_put_contents($attachmentName, $attachmentData);
                }
            }
        }
    }
    // process email content
}
imap_close($mailbox);

Conclusion: By using PHP’s mail, IMAP functions and libraries like PHPMailer, developers can reliably send and receive plain‑text, HTML, and attachment‑rich emails while ensuring proper encoding and display.