php generate strong password program

<?php
/**
  php生成强密码
  linK：www.jbxue.com 2013/3/2
*/
$password_length = 9;
function make_seed() {
list($usec, $sec) = explode(’ ‘, microtime());
return (float) $sec + ((float) $usec * 100000);
}
srand(make_seed());
$alfa = “1234567890qwertyuiopasdfghjklzxcvbnmQWERTYUIOPASDFGHJKLZXCVBNM”;
$token = “”;
for($i = 0; $i < $password_length; $i ++) {
$token .= $alfa[rand(0, strlen($alfa))];
}
echo $token;
//方法2
// Create Password
$totalChar = 8; // number of chars in the password
$salt = “abcdefghijklmnpqrstuvwxyzABCDEFGHIJKLMNPQRSTUVWXYZ123456789″; // salt to select chars from
srand((double)microtime()*1000000); // start the random generator
$Spass=””; // set the inital variable
for ($i=0;$i<$totalChar;$i++) // loop and create password
$Spass = $Spass . substr ($salt, rand() % strlen($salt), 1);