script captcha

[alexarpad2003]

Creati fisierul captcha.php in care o sa avem codul care genereaza o imagine captcha :

<?php 
session_start();// graphic  
header("content-type: image/png"); // type 
$image = imagecreate(100, 46); // size 
// BACKGROUND 
$achtergrond = imagecolorallocate($image, 234, 234, 234); 
// BLACK 
$zwart = imagecolorallocate($image, 0, 0, 0); 
// GRAY 
$grijs = imagecolorallocate($image, 200, 200, 200); 
// GREEN 
$groenb = imagecolorallocate($image, 133, 163, 174); 
// BORDER 
$bordercolor = imagecolorallocate($image,0,0,0); 
// draw some lines 
for($i=0;$i<12;$i++) 
{ 
    $x1 = rand(0,100); // random x- en y coordinaten voor de lijnen 
    $y1 = rand(0,100); 
    $x2 = rand(0,100); 
    $y2 = rand(0,100); 
    imageline($image,$x1,$y1,$x2,$y2,$grijs); 

} 
// random text 
$input = array(    'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm',  
                   'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z', 
                '1', '2', '3', '4', '5', '6', '7', '8', '9', '0'); 

$rand_keys = array_rand($input, 5); // 5 random tekens selecteren uit de array 
$int_x = 15; // startp x 
$int_y = 25; // startp y 
$tekens = ''; 
for($i=0; $i<5; $i++) 
{//place signs 
    $font_kleur1 = rand(50,200); // variate colors  
    $font_kleur2 = rand(50,200); 
    $font_kleur3 = rand(50,200); 
    $random_kleur = imagecolorallocate($image, $font_kleur1, $font_kleur2, $font_kleur3); 
    // place some extra pixels 
    for($y=0;$y<50;$y++) 
    { 
        $pixel_x_rand = rand(0,100); // random coordinaten 
        $pixel_y_rand = rand(0,50); 
        imagesetpixel($image, $pixel_x_rand, $pixel_y_rand, $random_kleur); 
        imagesetpixel($image, $pixel_x_rand+1, $pixel_y_rand+1, $random_kleur); 
        $y++; 
    } 
    $grootte_tekst = rand(13,15); // text size   
    $font = 'verdanab.ttf'; // TrueType Font loaded from file 
    $angle_rand = rand(-20,20); 
    imagettftext($image, $grootte_tekst, $angle_rand, $int_x, $int_y, $random_kleur, $font, $input[$rand_keys[$i]]); 
    $regels = ''; 
    $tekens .= $input[$rand_keys[$i]];  
    $int_x = $int_x + 15; 
    $random_y = rand(5,15); 
    $int_y = ($int_y >= 26 ? $int_y - $random_y : $int_y + $random_y); 

} 
imagerectangle($image,0,0,99,45,$bordercolor); 
$_SESSION['captcha'] = $tekens; 
imagepng($image);  
imagedestroy($image); 
?>

Aveti nevoie de fontul verdanab.ttf pe care il puteti downloada de aici si care trebuie sa fie in acelasi folder cu captcha.php .

Urmatorul cod poate fi pus intr-o pagina de register, upload, login, unde vreti voi sa se afle imaginea captcha si formul cu inputul ce face validarea captcha-ului :

<?php
session_start();
if ($_POST['submit'])
{
if ($_POST['captcha']==$_SESSION['captcha']) header('Location:http://www.google.ro'); 
else $eroare='codul nu este bun';
}

?>

<img src="captcha.php" alt="CAPTCHA" /><br/>
<form name="formular" method="post" action="">
<input type="text" name="captcha" />
<input type="submit" value="submit" name="submit"><br/>
<?php echo $eroare;?>

Sursa : www.opensc.ws

Edited August 2, 2011 by alexarpad2003