PHP验证码图片

AuthImg.php[CODE:]

session_start();
/* 
 *   Filename: authimg.php 
 *   Author:   hutuworm 
 *   Date:     2003-04-28 
 *   @Copyleft hutuworm.org 
 */ 
Header("Content-type: image/PNG");  
srand((double)microtime()*1000000); 
$im = imagecreate(62,20); 
$black = ImageColorAllocate($im, 0,0,0); 
$white = ImageColorAllocate($im, 255,255,255); 
$gray = ImageColorAllocate($im, 200,200,200); 
imagefill($im,0,0,$gray); 
while(($authnum=rand()%100000)<10000);
imagestring($im, 5, 10, 3, $authnum, $black); 
for($i=0;$i<200;$i++){ 
    $randcolor = ImageColorallocate($im,rand(0,255),rand(0,255),rand(0,255));
    imagesetpixel($im, rand()%70 , rand()%30 , $randcolor); 
} 
$_SESSION['authnum']=$authnum;
ImagePNG($im); 
ImageDestroy($im); 
?>

使用方法：[CODE:]

0>

认证页：[CODE:]

if($_SESSION['authnum']==$_POST["VerifyCode"]){ 
    $link -> Inf_right("正确！");
}else{ 
    $link -> Inf_wrong("验证码输入错误！");
}

很快很方便~！