Two PHP codes for generating graphic verification codes_PHP tutorial

Verification codes are often used in PHP. Below we provide you with some PHP verification code generation classes and programs. You can just copy them and use them directly. See the code below.

Verification codes are often used in PHP tutorials. Below we provide you with some PHP verification code generation classes and programs. You can just copy them and use them directly. See the code below.

session_start();
Header("Content-type: image/gif");
class SecurityCode
{
private $codes = '';
function __construct()
{
$code = '0-1-2-3-4-5-6-7-8-9-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';
$codeArray = explode('-',$code);
shuffle($codeArray);
$this->codes = implode('',array_slice($codeArray,0,4));
}
public function CreateImg()
{
$_SESSION['check_pic'] = $this->codes;
$img = imagecreate(70,25);
imagecolorallocate($img,222,222,222);
$testcolor1 = imagecolorallocate($img,255,0,0);
$testcolor2 = imagecolorallocate($img,51,51,51);
$testcolor3 = imagecolorallocate($img,0,0,255);
$testcolor4 = imagecolorallocate($img,255,0,255);
for ($i = 0; $i < 4; $i++)
{
imagestring($img,rand(5,6),8 + $i * 15,rand(2,8),$this->codes[$i],rand(1,4));
}
imagegif($img);
}
}
$code = new SecurityCode();
$code->CreateImg();
$code = NULL;
?>

Code 2

session_start();
for($i=0; $i<4; $i++){
$rand.= dechex(rand(1,15));
}
$_SESSION[check_pic]=$rand;
//echo $_SESSION[check_pic];
//Set image size">Image size
$im = imagecreatetruecolor(100,30);
// Set color
$bg=imagecolorallocate($im,0,0,0);
$te=imagecolorallocate($im,255,255,255);
//Write the string in the upper left corner of the image
imagestring($im,rand(5,6),rand(25,30),5,$rand,$te);
// Output image
header("Content-type:image/jpeg");
imagejpeg($im);
?>