<?php
session_start();
class CAPTCHA
{
private $objImage;
private $strQuestion;
private $strAnswer;
public function create_captcha()
{
$this->create_image();
$this->generate_random_question();
$this->write_question_on_image();
$this->apply_filters();
$this->show_image();
$_SESSION['captcha'] = $this->strAnswer;
imagedestroy($this->objImage);
}
private function create_image()
{
$this->objImage = imagecreatetruecolor(150,80);
$intColor = imagecolorallocate($this->objImage,rand(10,255),rand(10,255),rand(10,255));
imagefill($this->objImage,100,40,$intColor);
}
private function generate_random_question()
{
$arrOperands = array('+','-','*');
$arrOperandShows = array('+','-',chr(215));
$intRandIndex = rand(0,count($arrOperands)-1);
$strOperand = $arrOperands[$intRandIndex];
$strOperandShow = $arrOperandShows[$intRandIndex];
$intNum1 = rand(1,9);
$intNum2 = rand(1,$intNum1);
$this->strQuestion = "$intNum1 $strOperandShow $intNum2";
$strEval = "\$intAnswer = $intNum1 $strOperand $intNum2;";
eval($strEval);
$this->strAnswer = $intAnswer;
}
private function write_question_on_image()
{
$intColor = imagecolorallocate($this->objImage,0,0,0);
$intAngle = rand(-10,10);
imagettftext($this->objImage,18,$intAngle,50,50,$intColor,'tahoma.ttf',$this->strQuestion);
}
private function apply_filters()
{
imagefilter($this->objImage,IMG_FILTER_GAUSSIAN_BLUR);
}
private function show_image()
{
header("Content-type: image/png");
imagepng($this->objImage);
}
}
$objCaptcha = new CAPTCHA();
$objCaptcha->create_captcha();
?>
. این شکی توش نیست
