<?php
$text    = '89114001234';
$regexp1 = '/^8[0-9]{10}$/';
$regexp2 = '/^8[(]([0-9]{3})[)][-]([0-9]{3})[ ]([0-9]{2})[ ]([0-9]{2})$/';
$regexp3 = '/^8[-]([0-9]{3})[-]([0-9]{3})[-]([0-9]{2})[-]([0-9]{2})$/';
if ((preg_match($regexp1, $text))  && (preg_match($regexp2, $text)) && (preg_match($regexp3, $text))) {
    echo "Все верно.\n";
} else {
    echo "Укажите номер в  формате «8(ххх)-ххх хх хх», «8-ххх-ххх-хх-хх» или «8хххххххххх»!\n";
}

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