验证码类

ゝ一纸荒年。 2021-10-01 10:32 321阅读 0赞

> 验证码类 captcha.class.php

<?php
    class captcha{
        private $width;
        private $height;
        private $fontfile="mtcorsva.ttf";
        private $codeNum;
        private $code;
        private $im;
    
        function __construct($width=80, $height=20, $codeNum=4)
        {
            $this->width = $width;
            $this->height = $height;
            $this->codeNum = $codeNum;
        }
    
        public function showImg()
        {
            //创建图片
            $this->createImg();
            //设置干扰元素
            $this->setDisturb();
            //设置验证码
            $this->setCaptcha();
            //输出图片
            $this->outputImg();
        }
    
        public function getCaptcha()
        {
            return $this->code;
        }
    
        private function createImg()
        {
            $this->im = imagecreatetruecolor($this->width, $this->height);
            $bgColor = imagecolorallocate($this->im, 208, 208, 208);
            imagefill($this->im, 0, 0, $bgColor);
        }
    
        private function setDisturb()
        {
            $area = ($this->width * $this->height) / 20;
            $disturbNum = ($area > 250) ? 250 : $area;
            //加入点干扰
            // for ($i = 0; $i < $disturbNum; $i++) {
            //     $color = imagecolorallocate($this->im, rand(0, 255), rand(0, 255), rand(0, 255));
            //     imagesetpixel($this->im, rand(1, $this->width - 2), rand(1, $this->height - 2), $color);
            // }
            //加入弧线
            for ($i = 0; $i <= 5; $i++) {
                $color = imagecolorallocate($this->im, rand(128, 255), rand(125, 255), rand(100, 255));
                imagearc($this->im, rand(0, $this->width), rand(0, $this->height), rand(30, 300), rand(20, 200), 50, 30, $color);
            }
        }
    
        private function createCode()
        {
            $str = "23456789abcdefghijkmnpqrstuvwxyzABCDEFGHIJKMNPQRSTUVWXYZ";
    
            for ($i = 0; $i < $this->codeNum; $i++) {
                $this->code .= $str{rand(0, strlen($str) - 1)};
            }
        }
    
        private function setCaptcha()
        {
            $this->createCode();
    
            for ($i = 0; $i < $this->codeNum; $i++) {
                $color = imagecolorallocate($this->im, rand(0, 50), rand(50, 250), rand(0, 250));
                $size = rand(floor($this->height / 2), floor($this->height / 1.5));
                $x = floor($this->width / $this->codeNum) * $i + 5;
                $y = rand(floor($this->height / 2), floor($this->height / 1.2));
                //imagechar($this->im, $size, $x, $y, $this->code{$i}, $color);
                imagettftext($this->im, $size, 0, $x, $y, $color, $this->fontfile ,$this->code{$i});
            }
        }
    
        private function outputImg()
        {
            if (imagetypes() & IMG_JPG) {
                header('Content-type:image/jpeg');
                imagejpeg($this->im);
            } elseif (imagetypes() & IMG_GIF) {
                header('Content-type: image/gif');
                imagegif($this->im);
            } elseif (imagetype() & IMG_PNG) {
                header('Content-type: image/png');
                imagepng($this->im);
            } else {
                die("Don't support image type!");
            }
        }
        function __destruct(){
            imagedestroy($this->image);
        }
    }

> 生成验证码图片，验证码存入session imagecode.php

<?php
    session_start();
    $act  = isset($_GET['act']) ? trim($_GET['act']) : "";
    if($act=="verifycode")
    {
        $width   = isset($_GET['width']) ? intval(trim($_GET['width'])) : "120";
        $height  = isset($_GET['height']) ? intval(trim($_GET['height'])) : "40";
        require '../../captcha.class.php';
        $code = new captcha($width, $height, 4);
        $code->showImg();
        $_SESSION["verifycode"]= strtolower($code->getCaptcha());
    }

> 页面调用验证码