我需要在注册表单中添加一个简单的验证码，如单词验证码或数学验证码。但是代码不起作用。以下是代码:(请帮我修复代码）
<?php
session_start();
//random string generator function
function random($length){
//create a or array string called chars
$chars ="abcdefghijklmnopqrstuvwxyz23456789";
$str = "";
//is the variable which is equal to the length of the string called chars
$size = strlen($chars);
for($i=0; $i<$length; $i++){
$str .= $chars[rand(0, $size-1)];
}
return $str;
}
//the gd image adaptor in xampp
$cap = random(7);
$_SESSION['real'] = $cap;
$image = imagecreate(100, 20);
$background = imagecolorallocate($image, 0, 0, 0);
$foreground = imagecolorallocate($image, 255, 255, 255);
//this is going to write our string in the image
imagestring($image, 5,5,1,$cap,$foreground);
header("Content-type: image/jpeg");
imagejpeg($image);
?>
注册页码
<?php
//This function will display the registration form
function register_form(){
$date = date('D, M, Y');
echo "<form action='?act=register' method='post'>"
."Username: <input type='text' name='username' size='30'><br>"
."Password: <input type='password' name='password' size='30'><br>"
."Confirm your password: <input type='password' name='password_conf' size='30'><br>"
."Email: <input type='text' name='email' size='30'><br>"
."<img src= 'captcha.php'> <input type='text' name='captcha'<br>"
."<input type='hidden' name='date' value='$date'>"
."<input type='submit' value='Register'>"
."</form>";
}
//This function will register users data
function register(){
//Connecting to database
$connect = mysql_connect("localhost", "root", "nokiae71");
if(!$connect){
die(mysql_error());
}
//Selecting database
$select_db = mysql_select_db("forumStructure", $connect);
if(!$select_db){
die(mysql_error());
}
//Collecting info
$username = $_REQUEST['username'];
$password = $_REQUEST['password'];
$pass_conf = $_REQUEST['password_conf'];
$email = $_REQUEST['email'];
$date = $_REQUEST['date'];
$guess = $_POST['captcha'];
//Here we will check do we have all inputs filled
if(empty($username)){
die("Please enter your username!<br>");
}
if(empty($password)){
die("Please enter your password!<br>");
}
if(empty($pass_conf)){
die("Please confirm your password!<br>");
}
if(empty($email)){
die("Please enter your email!");
}
$real = (isset($_SESSION['real'])) ? $_SESSION['real'] : "";
if (empty($guess))
{
die("Please enter the correct CAPTCHA.<br>");
}
/*if ($real != $guess){
die("things are bad");
}*/
if (!empty($guess) && $guess !== $real)
{
die("Please enter the correct CAPTCHA.<br>");
}
//Let's check if this username is already in use
$user_check = mysql_query("SELECT username FROM users WHERE username='$username'");
$do_user_check = mysql_num_rows($user_check);
//Now if email is already in use
$email_check = mysql_query("SELECT email FROM users WHERE email='$email'");
$do_email_check = mysql_num_rows($email_check);
//Now display errors
if($do_user_check > 0){
die("Username is already in use!<br>");
}
if($do_email_check > 0){
die("Email is already in use!");
}
//Now let's check does passwords match
if($password != $pass_conf){
die("Passwords don't match!");
}
//If everything is okay let's register this user
$insert = mysql_query("INSERT INTO users (username, password, email) VALUES ('$username', '$password', '$email')");
if(!$insert){
die("There's little problem: ".mysql_error());
}
echo $username.", you are now registered. Thank you!<br><a href=login.php>Login</a> | <a href=index.php>Index</a>";
}
$act = isset($_GET['act']) ? $_GET['act'] : '';
switch($act){
default;
register_form();
break;
case "register";
register();
break;
}
?>
谢谢我只是php的新手，我想学习如何做到这一点。我在stackoverflow上获得了注册码仅用于学习目的...我们将非常感谢您的帮助或建议。
答案 0 :(得分：1)
你缺少session_start（）;在顶部和＆gt;在...上
<img src= 'captcha.php'> <input type='text' name='captcha'><br>"
答案 1 :(得分：0)
您可以使用此代码 -
<?php
//
// PHP module for easy utilization of the free captchas.net CAPTCHA service
//
// For documentation look at http://captchas.net/sample/php/
//
// Written by
// Sebastian Wilhelmi <seppi@seppi.de> and
// Felix Holderied <felix@holderied.de>
// This file is in the public domain.
//
// ChangeLog:
//
// 2014-04-27: Fixed missing initialization
//
// 2011-04-25: Added function captchas_image_reload
//
// 2011-03-08: Added color option (Alfred Vink)
//
// 2006-08-16: New optional features integrated
//
// 2006-03-01: Only delete the random string from the repository in
// case of a successful verification.
//
// 2006-02-14: Add new image() method returning an HTML/JavaScript
// snippet providing a fault tolerant service.
//
// 2005-06-02: Initial version.
//
class CaptchasDotNet
{
function CaptchasDotNet ($client, $secret,
$random_repository = '/tmp/captchasnet-random-strings',
$cleanup_time = 3600,
$alphabet = 'abcdefghijklmnopqrstuvwxyz',
$letters = 6,
$width = 240,
$height = 80,
$color = '000000'
)
{
$this->__client = $client;
$this->__secret = $secret;
$this->__random_repository = $random_repository;
$this->__cleanup_time = $cleanup_time;
$this->__time_stamp_file = $random_repository . '/__time_stamp__';
$this->__alphabet = $alphabet;
$this->__letters = $letters;
$this->__width = $width;
$this->__height = $height;
$this->__color = $color;
$this->__random_file = "";
}
function __random_string ()
{
// The random string shall consist of small letters, big letters
// and digits.
$letters = "abcdefghijklmnopqrstuvwxyz";
$letters .= strtoupper ($letters) + "0123456789";
// The random starts out empty, then 40 random possible characters
// are appended.
$random_string = '';
for ($i = 0; $i < 40; $i++)
{
$random_string .= $letters{rand (0, strlen ($letters) - 1)};
}
// Return the random string.
return $random_string;
}
// Create a new random string and register it.
function random ()
{
// If the repository directory is does not yet exist, create it.
if (!is_dir ($this->__random_repository))
{
mkdir ($this->__random_repository);
}
// If the time stamp file does not yet exist, create it.
if (!is_file ($this->__time_stamp_file))
{
touch ($this->__time_stamp_file);
}
// Get the current time.
$now = time ();
// Determine the time, before which to remove random strings.
$cleanup_time = $now - $this->__cleanup_time;
// If the last cleanup is older than specified, cleanup the
// directory.
if (filemtime ($this->__time_stamp_file) < $cleanup_time)
{
$handle = opendir ($this->__random_repository);
while (true)
{
$filename = readdir ($handle);
if (!$filename)
{
break;
}
if ($filename != '.' && $filename != '..')
{
$filename = $this->__random_repository . '/' . $filename;
if (filemtime ($filename) < $cleanup_time)
{
unlink ($filename);
}
}
}
closedir ($handle);
touch ($this->__time_stamp_file);
}
// loop until a valid random string has been found and registered,
// but at most 20 times. If no valid random has been found during
// that time, there is something really wrong. Also show the error
// in the last run.
for ($remaining = 20; $remaining > 0; $remaining--)
{
// generate a new random string.
$random = $this->__random_string ();
// open a file with the corresponding name in the repository
// directory in such a way, that the creation fails, when the
// file already exists. That should be near to impossible with
// good seeding of the random number generator, but it's better
// to play safe. If this is the last run, show the possible
// error message.
$filename = $this->__random_repository . '/' . $random;
if ($remaining == 1)
{
$file = fopen ($filename, 'x');
}
else
{
$file = @fopen ($filename, 'x');
}
if ($file)
{
fclose ($file);
break;
}
// if the file already existed, rerun the loop to try the next
// string.
}
// return the successfully registered random string.
$this->__random = $random;
return $random;
}
//
// Generates image-URL Parameters are only atached if different from default
//
function image_url ($random = False, $base = 'http://image.captchas.net/')
{
if (!$random)
{
$random = $this->__random;
}
$image_url = $base;
$image_url .= '?client=' . $this->__client;
$image_url .= '&random=' . $random;
if ($this->__alphabet!='abcdefghijklmnopqrstuvwxyz') {$image_url .= '&alphabet=' . $this->__alphabet;};
if ($this->__letters!=6) {$image_url .= '&letters=' . $this->__letters;};
if ($this->__width!=240) {$image_url .= '&width=' . $this->__width;};
if ($this->__height!=80) {$image_url .= '&height=' . $this->__height;};
if ($this->__color!='000000') {$image_url .= '&color=' . $this->__color;};
return $image_url;
}
//
// Same as image_url but without width and height
//
function audio_url ($random = False, $base = 'http://audio.captchas.net/')
{
if (!$random)
{
$random = $this->__random;
}
$audio_url = $base;
$audio_url .= '?client=' . $this->__client;
$audio_url .= '&random=' . $random;
if ($this->__alphabet!='abcdefghijklmnopqrstuvwxyz') {$audio_url .= '&alphabet=' . $this->__alphabet;};
if ($this->__letters!=6) {$audio_url .= '&letters=' . $this->__letters;};
return $audio_url;
}
//
// Generates complete html-sample with javascript to reload image from
// backup server
//
function image ($random = False, $id = 'captchas.net')
{
$image = <<<EOT
<a href="http://captchas.net"><img
style="border: none; vertical-align: bottom"
id="@ID@" src="@URL@" width="@WIDTH@" height="@HEIGHT@"
alt="The Captcha image" /></a>
<script type="text/javascript">
<!--
function captchas_image_reload (imgId)
{
var image_url = document.getElementById(imgId).src;
image_url+= "&";
document.getElementById(imgId).src = image_url;
}
function captchas_image_error (image)
{
if (!image.timeout) return true;
image.src = image.src.replace (/^http:\/\/image\.captchas\.net/,
'http://image.backup.captchas.net');
return captchas_image_loaded (image);
}
function captchas_image_loaded (image)
{
if (!image.timeout) return true;
window.clearTimeout (image.timeout);
image.timeout = false;
return true;
}
var image = document.getElementById ('@ID@');
image.onerror = function() {return captchas_image_error (image);};
image.onload = function() {return captchas_image_loaded (image);};
image.timeout
= window.setTimeout(
"captchas_image_error (document.getElementById ('@ID@'))",
10000);
image.src = image.src;
//-->
</script>
EOT;
$image = str_replace ('@HEIGHT@', $this->__height, $image);
$image = str_replace ('@WIDTH@', $this->__width, $image);
$image = str_replace ('@ID@', $id, $image);
$image = str_replace ('@URL@', $this->image_url (), $image);
return $image;
}
function validate ($random)
{
$this->__random = $random;
$file_name = $this->__random_repository . '/' . $random;
// Find out, whether the file exists
$result = is_file ($file_name);
// if the file exists, remember it.
if ($result)
{
$this->__random_file = $file_name;
}
// the random string was valid, if and only if the corresponding
// file existed.
return $result;
}
function verify ($input, $random = False)
{
if (!$random)
{
$random = $this->__random;
}
$password_letters = $this->__alphabet;
$password_length = $this->__letters;
// If the user input has the wrong lenght, it can't be correct.
if (strlen ($input) != $password_length)
{
return False;
}
// Calculate the MD5 digest of the concatenation of secret key and
// random string. The digest is a hex string.
$encryption_base = $this->__secret . $random;
// This extension is needed for secure use of optional parameters
// In case of standard use we do not append the values, to be
// compatible to existing implementations
if(($password_letters != 'abcdefghijklmnopqrstuvwxyz') || ($password_length != '6'))
{
$encryption_base = $encryption_base . ':' . $password_letters . ':' . $password_length;
}
$digest = md5 ($encryption_base);
// Check the password according to the rules from the first
// positions of the digest.
for ($pos = 0; $pos < $password_length; $pos++)
{
$letter_num
= hexdec (substr ($digest, 2 * $pos, 2)) % strlen ($password_letters);
// If the letter at the current position is wrong, the user
// input isn't correct.
if ($input[$pos] != $password_letters[$letter_num])
{
return False;
}
}
// if the file exists, remove it.
if ($this->__random_file)
{
unlink ($this->__random_file);
unset ($this->__random_file);
}
// The user input was correct.
return True;
}
}
?>
这是图书馆。
现在是HTML代码 -
<?php
require 'CaptchasDotNet.php';
// Required Parameters
// Replace the values you receive upon registration at http://captchas.net.
//
// client: 'demo'
//
// secret: 'secret'
//
// Optional Parameters and defaults
//
// repository_prefix: '/tmp/captchasnet-random-strings' path to repository
// ATTENTION SAFE-MODE, YOU HAVE TO CHOOSE SOMETHING LIKE
// '/writable/path/captchasnet-random-strings'
//
// cleanup_time: '3600' (means max 1 hour between query and check)
//
// alphabet: 'abcdefghijklmnopqrstuvwxyz' (Used characters in captcha)
// We recommend alphabet without ijl: 'abcdefghkmnopqrstuvwxyz'
//
// letters: '6' (Number of characters in captcha)
//
// width: '240' (image width)
//
// height: '80' (image height)
//
// color: '000000' (image color in rgb)
//
// language: 'en' (audio language, append &language=fr/de/it/nl to audio-url)
//
// Usage
// $captchas = new CaptchasDotNet (<client>, <secret>,
// <repository_prefix>, <cleanup_time>,
// <alphabet>,<letters>,
// <height>,<width>,<color>);
//
// Don't forget same settings in check.php
// Construct the captchas object.
$captchas = new CaptchasDotNet ('demo', 'secret',
'/tmp/captchasnet-random-strings','3600',
'abcdefghkmnopqrstuvwxyz','6',
'240','80','000088');
?>
<html>
<head>
<title>Sample PHP CAPTCHA Query</title>
</head>
<h1>Sample PHP CAPTCHA Query</h1>
<form method="get" action="check.php">
<table>
<tr>
<td>
<input type="hidden" name="random" value="<?= $captchas->random () ?>" />
Your message:</td><td><input name="message" size="60" />
</td>
</tr>
<tr>
<td>
The CAPTCHA password:
</td>
<td>
<input name="password" size="6" />
</td>
</tr>
<tr>
<td>
</td>
<td>
<?= $captchas->image () ?> <a href="javascript:captchas_image_reload('captchas.net')">Reload Image</a>
<br> <a href="<?= $captchas->audio_url () ?>">Phonetic spelling (mp3)</a>
<br> <a href="<?= $captchas->audio_url () ?>&language=de">Buchstabieren (mp3)</a>
<br> <a href="<?= $captchas->audio_url () ?>&language=it">Compitare (mp3)</a>
<br> <a href="<?= $captchas->audio_url () ?>&language=nl">Spellen (mp3)</a>
<br> <a href="<?= $captchas->audio_url () ?>&language=fr">Epeler (mp3)</a>
</td>
</tr>
<tr>
<td>
</td>
<td>
<input type="submit" value="Submit" />
</td>
</tr>
</table>
现在检查 -
<?php
require 'CaptchasDotNet.php';
// See query.php for documentation
$captchas = new CaptchasDotNet ('demo', 'secret',
'/tmp/captchasnet-random-strings','3600',
'abcdefghkmnopqrstuvwxyz','6',
'240','80','000088');
// Read the form values
$message = $_REQUEST['message'];
$password = $_REQUEST['password'];
$random_string = $_REQUEST['random'];
?>
<html>
<head>
<title>Sample PHP CAPTCHA Query</title>
</head>
<h1>Sample PHP CAPTCHA Query</h1>
<?php
// Check the random string to be valid and return an error message
// otherwise.
if (!$captchas->validate ($random_string))
{
echo 'The session key (random) does not exist, please go back and reload form.<br/>';
echo 'In case you are the administrator of this page, ';
echo 'please check if random keys are stored correct.<br/>';
echo 'See http://captchas.net/sample/php/ "Problems with save mode"';
}
// Check, that the right CAPTCHA password has been entered and
// return an error message otherwise.
elseif (!$captchas->verify ($password))
{
echo 'You entered the wrong password. Aren\'t you human? Please use back button and reload.';
}
// Return a success message
else
{
echo 'Your message was verified to be entered by a human and is "' . $message . '"';
}
?>
</html>
想想，它会对你有所帮助