可以指定產生的字串長度
function rand_str($length, $max=FALSE)
{
if (is_int($max) && $max > $length)
{
$length = mt_rand($length, $max);
}
$output = '';
for ($i=0; $i<$length; $i++)
{
$which = mt_rand(0,2);
if ($which === 0)
{
$output .= mt_rand(0,9);
}
elseif ($which === 1)
{
$output .= chr(mt_rand(65,90));
}
else
{
$output .= chr(mt_rand(97,122));
}
}
return $output;
}
調用執行個體:
$randstr = rand_str(16);
產生隨機字串的函數
<?php
/**
* 產生隨機字串
*
* 產生一個指定長度的隨機字串,並返回給使用者
*
* @access public
* @param int $len 產生字串的位元
* @return string
*/
function randStr($len=6) {
$chars='ABDEFGHJKLMNPQRSTVWXYabdefghijkmnpqrstvwxy23456789#%*'; // characters to build the password from
mt_srand((double)microtime()*1000000*getmypid()); // seed the random number generater (must be done)
$password='';
while(strlen($password)<$len)
$password.=substr($chars,(mt_rand()%strlen($chars)),1);
return $password;
}
?>
建立字元池。
function randomkeys($length)
{
$pattern = '1234567890abcdefghijklmnopqrstuvwxyz
ABCDEFGHIJKLOMNOPQRSTUVWXYZ,./&l
t;>?;#:@~[]{}-_=+)(*&^%$?!'; //字元池
for($i=0; $i<$length; $i++)
{
$key .= $pattern{mt_rand(0,35)}; //產生php隨機數
}
return $key;
}
echo randomkeys(8);
無需建立字元池
function randomkeys($length)
{
$output='';
for ($a = 0; $a < $length; $a++) {
$output .= chr(mt_rand(35, 126)); //產生php隨機數
}
return $output;
}
echo randomkeys(8);
隨機使用者名稱和隨機密碼例子
//隨機產生使用者名稱(長度6-13)
function create_password($pw_length = 4){
$randpwd = '';
for ($i = 0; $i < $pw_length; $i++){
$randpwd .= chr(mt_rand(33, 126));
}
return $randpwd;
}
function generate_username( $length = 6 ) {
// 密碼字元集,可任意添加你需要的字元
$chars = 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789!@#$%^&*()-_ []{}<>~`+=,.;:/?|';
$password = '';
for ( $i = 0; $i < $length; $i++ )
{
// 這裡提供兩種字元擷取方式
// 第一種是使用substr 截取$chars中的任意一位字元;
// 第二種是取字元數組$chars 的任意元素
// $password .= substr($chars, mt_rand(0, strlen($chars) - 1), 1);
$password .= $chars[ mt_rand(0, strlen($chars) - 1) ];
}
return $password;
}
//調用
$userId = 'user'.generate_username(6);
$pwd = create_password(9);
mt_srand產生隨機種子,密碼的長度可以隨意定義,最長32位。
<?php
mt_srand((double) microtime() * 1000000);
function gen_random_password($password_length = 32, $generated_password = ""){
$valid_characters = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789";
$chars_length = strlen($valid_characters) - 1;
for($i = $password_length; $i--; ) {
//$generated_password .= $valid_characters[mt_rand(0, $chars_length)];
$generated_password .= substr($valid_characters, (mt_rand()%(strlen($valid_characters))), 1);
}
return $generated_password;
}
?>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<title>php密碼產生器</title>
<style type="text/css">
body {
font-family: Arial;
font-size: 10pt;
}
</style>
</head>
<body>
<span style="font-weight: bold; font-size: 15pt;">密碼產生器</span><br /><br />
<?php
if (isset($_GET['password_length'])){
if(preg_match("/([0-9]{1,8})/", $_GET['password_length'])){
print("密碼產生成功:<br />
<span style="font-weight: bold">" . gen_random_password($_GET['password_length']) . "</span><br /><br />n");
} else {
print("密碼長度不正確!<br /><br />n");
}
}
print <<< end
請為密碼產生其指定產生密碼的長度:<br /><br />
<form action="{$_SERVER['PHP_SELF']}" method="get">
<input type="text" name="password_length">
<input type="submit" value="產生">
</form>
end;
?>
</body>
</html>