controlli campi email

[rocco.mod]

ciao alcio e grazie un altra cosa , come potrei fare un controllo al campo captcha? ti posto lo script originale

if (isset($_POST['code']))
    echo (md5(strtoupper($_POST['code'])) == $_SESSION['__img_code__'])
        ? "Valid!" : "Invalid!"; 

ma vorrei che mi dasse se c e l errore e non s e giusto

questo invece e l immagine il files code.php

session_start();

require "_config.php";

$line_colors = preg_split("/,\s*?/", CODE_LINE_COLORS);
$char_colors = preg_split("/,\s*?/", CODE_CHAR_COLORS);
$fonts = collect_files(PATH_TTF, "ttf");

$img = imagecreatetruecolor(CODE_WIDTH, CODE_HEIGHT);
imagefilledrectangle($img, 0, 0, CODE_WIDTH - 1, CODE_HEIGHT - 1, gd_color(CODE_BG_COLOR));


// Draw lines

for ($i = 0; $i < CODE_LINES_COUNT; $i++)
    imageline($img,
        rand(0, CODE_WIDTH - 1),
        rand(0, CODE_HEIGHT - 1),
        rand(0, CODE_WIDTH - 1),
        rand(0, CODE_HEIGHT - 1),
        gd_color($line_colors[rand(0, count($line_colors) - 1)])
    );


// Draw code

$code = "";
$y = (CODE_HEIGHT / 2) + (CODE_FONT_SIZE / 2);
for ($i = 0; $i < CODE_CHARS_COUNT; $i++) {
    $color = gd_color($char_colors[rand(0, count($char_colors) - 1)]);
    $angle = rand(-30, 30);
    $char = substr(CODE_ALLOWED_CHARS, rand(0, strlen(CODE_ALLOWED_CHARS) - 1), 1);
    $font = PATH_TTF . "/" . $fonts[rand(0, count($fonts) - 1)];
    $x = (intval((CODE_WIDTH / CODE_CHARS_COUNT) * $i) + (CODE_FONT_SIZE / 2));
    $code .= $char;
    imagettftext($img, CODE_FONT_SIZE, $angle, $x, $y, $color, $font, $char);
}

$_SESSION['__img_code__'] = md5($code);

header("Content-Type: image/png");
imagepng($img);
imagedestroy($img);


function gd_color($html_color) {
    return preg_match('/^#?([\dA-F]{6})$/i', $html_color, $rgb)
      ? hexdec($rgb[1]) : false;
}


function collect_files($dir, $ext) {
    if (false !== ($dir = opendir($dir))) {
        $files = array();

        while (false !== ($file = readdir($dir)))
            if (preg_match("/\\.$ext\$/i", $file))
                $files[] = $file;

        return $files;

    } else
        return false;
} 

questo e il _config.php

define('CODE_WIDTH',         120);
define('CODE_HEIGHT',        30);
define('CODE_FONT_SIZE',     15);
define('CODE_CHARS_COUNT',   5);
define('CODE_LINES_COUNT',   10);
define('CODE_CHAR_COLORS',   "#880000,#008800,#000088,#888800,#880088,#008888,#000000");
define('CODE_LINE_COLORS',   "#DD6666,#66DD66,#6666DD,#DDDD66,#DD66DD,#66DDDD,#666666");
define('CODE_BG_COLOR',      "#FFFFFF");
define('CODE_ALLOWED_CHARS', "ABCDEFGHJKLMNPQRSTUVWXYZ2345689");
define('PATH_TTF',           "fonts");