<?php
 
error_reporting(-1);
 
$input = '8- (951)-4647- 425';
 
$parts = preg_split("/\\s|[(]|-|[)]/", $input, 0, PREG_SPLIT_NO_EMPTY); /* разбиваем номер на части по допустимым знакам*/
 
$phoneNoBullshit = implode("", $parts); /*Соединяем части, получая номер*/
 
$regExp = "/^(8|\\+7)\\d{10}$/";
 
if (preg_match($regExp, $phoneNoBullshit)) {
	echo "Yep, it's a phone number.";
} 
else {
	echo "Please, enter a real phone number WITHOUT BULLSHIT, not that crap you just typed.";
}
?>
 

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