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Example (v příloze dva jpg, změň Content-Type pokud tam nebude jpg)

<?php

$mailto = "to@example";
$subject = "Jaké bych si přála počasí";
$message = "Přála bych si mít tolik sněhu jako loni v únoru.";
$file1 = "priloha1.jpg";
$file2 = "priloha2.jpg";

$separator = md5(time());

$subject = "=?utf-8?B?".base64_encode($subject)."?=";

$headers = "From: =?UTF-8?B?".base64_encode("Eliška")."?=<from@example>".PHP_EOL;
$headers .= "MIME-Version: 1.0".PHP_EOL;
$headers .= "Content-Type: multipart/mixed; boundary=\"".$separator."\"";

$body = "--".$separator.PHP_EOL;

$body .= "Content-Type: text/plain; charset=UTF-8".PHP_EOL;
$body .= "Content-Transfer-Encoding: base64".PHP_EOL.PHP_EOL;
$body .= base64_encode($message).PHP_EOL;

$body .= "--".$separator.PHP_EOL;

$body .= "Content-Type: image/jpeg; name=\"".$file1."\"".PHP_EOL;
$body .= "Content-Transfer-Encoding: base64".PHP_EOL;
$body .= "Content-Disposition: attachment; size=".filesize($file1)."; filename=\"".$file1."\"" . PHP_EOL . PHP_EOL;
$body .= chunk_split(base64_encode(file_get_contents($file1))).PHP_EOL;

$body .= "--".$separator.PHP_EOL;

$body .= "Content-Type: image/jpeg; name=\"".$file2."\"".PHP_EOL;
$body .= "Content-Transfer-Encoding: base64".PHP_EOL;
$body .= "Content-Disposition: attachment; size=".filesize($file2)."; filename=\"".$file2."\"" . PHP_EOL . PHP_EOL;
$body .= chunk_split(base64_encode(file_get_contents($file2))).PHP_EOL;

$body .= "--".$separator."--";

if (mail($mailto, $subject, $body, $headers)) echo "mail send ... OK";