可以按照指定的长度生成随机密码

function generatePassword($length=9, $strength=0) { 
$vowels = 'aeuy'; 
$consonants = 'bdghjmnpqrstvz'; 
if ($strength >= 1) { 
$consonants .= 'BDGHJLMNPQRSTVWXZ'; 
} 
if ($strength >= 2) { 
$vowels .= "AEUY"; 
} 
if ($strength >= 4) { 
$consonants .= '23456789'; 
} 
if ($strength >= 8 ) { 
$vowels .= '@#$%'; 
} 
$password = ''; 
$alt = time() % 2; 
for ($i = 0; $i < $length; $i++) { 
if ($alt == 1) { 
$password .= $consonants[(rand() % strlen($consonants))]; 
$alt = 0; 
} else { 
$password .= $vowels[(rand() % strlen($vowels))]; 
$alt = 1; 
} 
} 
return $password; 
}