Two ways to automatically generate new passwords in php

/*
 * php automatically generates a new password custom function
 Applicable environment: PHP5.2.x / mysql 5.0.x
 Code author: xujiajay
* */
function genPassword($ min = 5, $max = 8)
{
 $validchars="abcdefghijklmnopqrstuvwxyz123456789";
 $max_char=strlen($validchars)-1;
 $length=mt_rand($min,$max);
 $password = "" ;
 for($i=0;$i<$length;$i )
 {
 $password.=$validchars[mt_rand(0,$max_char)];
 }
 return $password;
}
echo "New Password: ".genPassword()."";
echo "New password: ".genPassword(5,10)."";
?>

Method 2:

/**
 php generate random password
*/
function generatePassword($length=8)
{
 $chars = array_merge(range(0,9),
 range ('a','z'),
 range('A','Z'),
 array('!','@','$','%','^','&',' *'));
 shuffle($chars);
 $password = '';
 for($i=0; $i<8; $i++) {
 $password .= $chars[$i];
 }
 return $password;
}
echo "New password:" . generatePassword(16);
?>