E-Mail addresses validate

#done#integritaet#integrity#php#spam#validation#validieren

e-mail spam protect vaD often used method (jIH je): registration Daq valid mail address nob pagh. "sapdojapjdspefjfejfos@dfioshdfiosfho.de" vIlo' (validation mail send pagh Sov 'ej information few neH poQ, mail address nob neH pagh, SPAM risk pagh). legitimate. 'ach site operators valid e-mail addresses neH system Daq neH.

chay' guarantee laH?

obvious: verification mail send. user double-opt-in via link mail address validate poQ. validation qaSDI' neH data access. decisive disadvantage ghaj: user valid e-mail address nob 'ach validation mail expect pagh, annoyed link click again - information skip.

verification mail skip neH 'ach protection some valid address vaD?

Step 1: correct e-mail syntax validate

e-mail addresses (Internet Daq, SMTP common mail servers) pattern: localpart@domainpart.tld misvam: meine-fancy-mailadresse@devdave.de

rudimentary protection vaD mail address validate via

if (filter_var($email_address, FILTER_VALIDATE_EMAIL)) {
  echo "Mailadresse gültig";
}

inputs:

asdadasd
asddasd@asdasd
.asd§@dfsdf

sorted out.

Step 2: MX Record validate

article point 'oH. MX Record (Mail Exchange Resource Record) FQDN (Full Qualified Domain Name) mail server nuqDaq reachable jatlh. jIH MX record Uberspace mail server point (Uberspace via mails process forward). domain MX record pagh pagh domain found pagh vaj recipient e-mails domain via receive laHbe' (logical). chay' check?

$valid = checkdnsrr($email_address, "MX");
echo "Mailadresse " . ($valid ? "" : "un") . " gültig";

checkdnsrr (Check DNS Resource Record) valid MX record tu'be' vaj mail address invalid 'ej again ask poQ.

spam neH pagh 'ach mails receive neH? temporary mail addresses vIlegh'a'?