/**
 * PHP从数据库查询email是否已经存在
 *
 * @param 
 * @author 网： jb51.cc
 **/
// Use this
$email_is_valid = valid_email($email,$db);
// Function
function valid_email ($email,$db) {
	$r_email = $db->prepare('SELECT COUNT(id) FROM inscriptions WHERE email = ?');
	$r_email->execute(array($email));
	$r_email_count = $r_email->fetchAll();
	if ($r_email_count[0][0] == 0):
		if (!filter_var($email,FILTER_VALIDATE_EMAIL)):
			return true;
		else:
			return false;
		endif;      
	else:
		return true;
	endif;
}
/***   来自编程之家 jb51.cc（jb51.cc）   ***/