<?php
header("Content-Type: text/plain; charset=utf-8");
error_reporting(E_ALL | E_STRICT);
 
$goodnumbers = array('84951234567', '+74951234567', '8-495-1-234-567', ' 8 (8122) 56-56-56', '8-911-1234567', '8 (911) 12 345 67', '8-911 12 345 67', '8 (911) - 123 - 45 - 67', '+ 7 999 123 4567', '8 ( 999 ) 1234567', '8 999 123 4567');
 
$badnumbers = array('02', '84951234567 позвать люсю', '849512345', '849512345678',
    '8 (409) 123-123-123', '7900123467', '5005005001', '8888-8888-88',
    '84951a234567', '8495123456a',
    '+1 234 5678901', // неверный код страны
    '+8 234 5678901', // либо 8 либо +7
    '7 234 5678901' // нет +
);
 
$regexp = '/^\s?(8|\+[\s]?7)([\s()-]{0,}\d{1}[\s()-]{0,}\d{1}[\s()-]{0,}\d{1}[\s()-]{0,}\d{1}[\s()-]{0,}\d{1}[\s()-]{0,}\d{1}[\s()-]{0,}\d{1}[\s()-]{0,}\d{1}[\s()-]{0,}\d{1}[\s()-]{0,}\d{1}[\s()-]{0,})$/';
echo "Проверяем правильные номера: \n";
 
foreach($goodnumbers as $value){
    if(preg_match($regexp, $value)){
        echo "Номер правильный {$value}\n";
    }else {
        echo "Номер неправильный  {$value}\n";
    }
}
 
echo "\nПроверяем неправильные номера: \n";
 
foreach($badnumbers as $value){
    if(preg_match($regexp, $value)){
        echo "Номер правильный {$value}\n";
    }else {
        echo "Номер неправильный  {$value}\n";
    }
}

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