<?php class Vcode { private $width; //宽 private $height; //高 private $num; //数量 private $code; //验证码 private $img; //图像的资源 //构造方法， 三个参数 function __construct($width=80, $height=20, $num=4) { $this->width = $width; $this->height = $height; $this->num = $num; $this->code = $this->createcode(); //调用自己的方法 } //获取字符的验证码， 用于保存在服务器中 function getcode() { return $this->code; } //输出图像 function outimg() { //创建背景 (颜色， 大小， 边框) $this->createback(); //画字 (大小， 字体颜色) $this->outstring(); //干扰元素(点， 线条) $this->setdisturbcolor(); //输出图像 $this->printimg(); } //创建背景 private function createback() { //创建资源 $this->img = imagecreatetruecolor($this->width, $this->height); //设置随机的背景颜色 $bgcolor = imagecolorallocate($this->img, rand(225, 255), rand(225, 255), rand(225, 255)); //设置背景填充 imagefill($this->img, 0, 0, $bgcolor); //画边框 $bordercolor = imagecolorallocate($this->img, 0, 0, 0); imagerectangle($this->img, 0, 0, $this->width-1, $this->height-1, $bordercolor); } //画字 private function outstring() { for($i=0; $i<$this->num; $i++) { $color= imagecolorallocate($this->img, rand(0, 128), rand(0, 128), rand(0, 128)); $fontsize=rand(3,5); //字体大小 $x = 3+($this->width/$this->num)*$i; //水平位置 $y = rand(0, imagefontheight($fontsize)-3); //画出每个字符 imagechar($this->img, $fontsize, $x, $y, $this->code{$i}, $color); } } //设置干扰元素 private function setdisturbcolor() { //加上点数 for($i=0; $i<100; $i++) { $color= imagecolorallocate($this->img, rand(0, 255), rand(0, 255), rand(0, 255)); imagesetpixel($this->img, rand(1, $this->width-2), rand(1, $this->height-2), $color); } //加线条 for($i=0; $i<10; $i++) { $color= imagecolorallocate($this->img, rand(0, 255), rand(0, 128), rand(0, 255)); imagearc($this->img,rand(-10, $this->width+10), rand(-10, $this->height+10), rand(30, 300), rand(30, 300), 55,44, $color); } } //输出图像 private function printimg() { if (imagetypes() & IMG_GIF) { header("Content-type: image/gif"); imagegif($this->img); } elseif (function_exists("imagejpeg")) { header("Content-type: image/jpeg"); imagegif($this->img); } elseif (imagetypes() & IMG_PNG) { header("Content-type: image/png"); imagegif($this->img); } else { die("No image support in this PHP server"); } } //生成验证码字符串 private function createcode() { $codes = "3456789abcdefghijkmnpqrstuvwxyABCDEFGHIJKLMNPQRSTUVWXY"; $code = ""; for($i=0; $i < $this->num; $i++) { $code .=$codes{rand(0, strlen($codes)-1)}; } return $code; } //用于自动销毁图像资源 function __destruct() { imagedestroy($this->img); } }<?php //开启session session_start(); include "vcode.class.php"; //构造方法 $vcode = new Vcode(80, 30, 4); //将验证码放到服务器自己的空间保存一份 $_SESSION['code'] = $vcode->getcode(); //将验证码图片输出 $vcode->outimg();?><?php session_start();if(isset($_POST['dosubmit'])) { if(strtoupper($_SESSION['code']) == strtoupper($_POST['code']) ) { echo "输入成功!<br>"; }else{ echo "输入不对!<br>"; }}?> <body> <form action="reg.php" method="post"> username: <input type="text" name="username"> <br> password: <input type="password" name="password"> <br> code: <input type="text" onkeyup="if(this.value!=this.value.toUpperCase()) this.value=this.value.toUpperCase()" size="6" name="code"> <img src="code.php" onclick="this.src='code.php?'+Math.random()" /> <br> <input type="submit" name="dosubmit" value="登 录"> <br> </form></body>压缩包在文件中