Ein kleines Script zum realisieren eines grafischen Captcha

Ein kleines Script zum realisieren eines grafischen Captcha

image.php

header("Content-type: image/png");

$string = "abcdefghijklmnopqrstuvwxyz0123456789";

for($i=0;$i<6;$i++){

    $pos = rand(0,36);

    $str .= $string{$pos};

}

$img_handle = ImageCreate (60, 20) or die ("Cannot Create image");

//Image size (x,y)

$back_color = ImageColorAllocate($img_handle, 255, 255, 255);

//Background color RBG

$txt_color = ImageColorAllocate($img_handle, 0, 0, 0);

//Text Color RBG

ImageString($img_handle, 31, 5, 0, $str, $txt_color);

Imagepng($img_handle);
session_start();

$_SESSION['img_number'] = $str;

?>[/php]

form.php
<form action="result.php" method="post">

<img alt="Random Number" src="image.php">

<input type="text" name="num"><br>

<input type="submit" name="submit" value="Check">

</form> 
result.php

session_start();

if($_SESSION['img_number'] != $_POST['num']){

echo'The number you entered doesn't match the image.<br>

<a href="form.php">Try Again</a><br>';

}else{

echo'The numbers Match!<br>

<a href="form.php">Try Again</a><br>;

}

?>[/php]

Der Code stammt von phpsnips.com