Простая графическая каптча, которую можно использовать в любых проектах

                        
image.php 

 

<?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; 

?>

 

 

 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 

 

<?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>'; 

} 

?>