78、PHP生成图片验证码demo【OOP面向对象版本】 · php笔记

下面是我今天下午用PHP写的一个生成图片验证码demo，仅供参考。文章底部提供demo在线预览地址。这个demo总共分为4个文件，具体代码如下： 1、code.html中的代码： <!doctype html> <html lang="en"> <head> <meta charset="utf-8" /> <title>登录、注册验证码生成</title> </head> <body>  <form action="checkcode.php" method="post"> <input type="text" name="code" /><br/> <img src="showcode.php" onclick="this.setAttribute('src','showcode.php?'+Math.random())" /> <span>看不清？点击图片即可切换验证码</span><br/> <input type="submit" name="sub" value="登录/注册" /> </form> </body> </html> 2、createcode.class.php中的代码： <?php class Createcode{ //画布资源 public $img; //画布宽度 private $img_width; //画布高度 private $img_height; //画布颜色 private $img_bgcolor; //验证码文字内容 private $str_content; //生成的验证码内容 private $code_content; //验证码颜色 private $code_content_color; //构造函数 public function __construct($img_width,$img_height,$str_content,$code_content_color){ if($this->gdcheck()){ $this->img_width = $img_width; $this->img_height = $img_height; $this->str_content = $str_content; $this->code_content_color = $code_content_color; $this->get_code(); $this->session_code(); } } //生成画布 public function get_img(){ //定义画布 $this->img = imagecreatetruecolor($this->img_width, $this->img_height); //画布背景色 $this->img_bgcolor = imagecolorallocate($this->img, mt_rand(0,255), mt_rand(0,255), mt_rand(0,255)); //给画图填充背景色 imagefill($this->img, 0, 0, $this->img_bgcolor); //取得画布的宽高 $img_width = imagesx($this->img); $img_height = imagesy($this->img); //画布中插入验证码 imagestring($this->img, 5, ($this->img_width/3), ($this->img_height/2.5), $this->code_content, imagecolorallocate($this->img, hexdec(substr($this->code_content_color, 1,2)), hexdec(substr($this->code_content_color, 3,2)), hexdec(substr($this->code_content_color, 5,2)))); //画布中插入像素点 $this->get_pix(); //画布中插入直线 $this->get_line(); //画布显示 header('Content-type:image/png'); imagepng($this->img); } //生成验证码 private function get_code(){ $str_content_len = strlen($this->str_content); for($i=0;$i<4;$i++){ $this->code_content .= substr($this->str_content, mt_rand(0,$str_content_len-1),1); } } //生成像素点 private function get_pix(){ for($j=0;$j<300;$j++){ $image_pix .= imagesetpixel($this->img, mt_rand(0,$this->img_width), mt_rand(0,$this->img_height), imagecolorallocate($this->img, mt_rand(0,255), mt_rand(0,255), mt_rand(0,255))); } return $image_pix; } //生成直线 private function get_line(){ for($l=0;$l<2;$l++){ $img_line .= imageline($this->img, mt_rand(0,$this->img_width), mt_rand(0,$this->img_height), mt_rand(0,$this->img_width), mt_rand(0,$this->img_height), imagecolorallocate($this->img, mt_rand(0,255), mt_rand(0,255), mt_rand(0,255))); } return $img_line; } //session存储验证码 private function session_code(){ session_start(); $_SESSION['code'] = $this->code_content; } //判断程序是否支持GD库 private function gdcheck(){ if(extension_loaded('gd')){ return true; }else{ return false; exit(); } } } 3、checkcode.php中的代码： <?php header('Content-type:text/html;charset="utf-8"'); session_start(); if($_POST['code']!=''){ if($_SESSION['code']==$_POST['code']){ echo '<script type="text/javascript"> alert("验证码填写成功"); history.go(-1); </script>'; }else{ echo '<script type="text/javascript"> alert("验证码填写失败"); history.go(-1); </script>'; } } 4、showcode.php中的代码： <?php function __autoload($classname){ include strtolower($classname).'.class.php'; } //定义验证码的取值范围 $str_content = 'abcdefghijklmnopqrstuvwxyz0123456789'; //验证码文字颜色 $code_content_color = '#ffffff'; //初始化对象 $code = new Createcode(100,30,$str_content,$code_content_color); $code->get_img();