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This article mainly introduces the verification code that can be refreshed by clicking PHP. Friends who are interested can refer to it. I hope it will be helpful to everyone.
Verification code class file CreateImg.class.php
<?php class ValidationCode { private $width,$height,$codenum; public $checkcode; //产生的验证码 private $checkimage; //验证码图片 private $disturbColor = ''; //干扰像素 function __construct($width='80',$height='20',$codenum='4') { $this->width=$width; $this->height=$height; $this->codenum=$codenum; } function outImg() { //输出头 $this->outFileHeader(); //产生验证码 $this->createCode(); //产生图片 $this->createImage(); //设置干扰像素 $this->setDisturbColor(); //往图片上写验证码 $this->writeCheckCodeToImage(); imagepng($this->checkimage); imagedestroy($this->checkimage); } private function outFileHeader() { header ("Content-type: image/png"); } private function createCode() { $this->checkcode = strtoupper(substr(md5(rand()),0,$this->codenum)); } private function createImage() { $this->checkimage = @imagecreate($this->width,$this->height); $back = imagecolorallocate($this->checkimage,255,255,255); $border = imagecolorallocate($this->checkimage,0,0,0); imagefilledrectangle($this->checkimage,0,0,$this->width - 1,$this->height - 1,$back); // 白色底 imagerectangle($this->checkimage,0,0,$this->width - 1,$this->height - 1,$border); // 黑色边框 } private function setDisturbColor() { for ($i=0;$i<=200;$i++) { $this->disturbColor = imagecolorallocate($this->checkimage, rand(0,255), rand(0,255), rand(0,255)); imagesetpixel($this->checkimage,rand(2,128),rand(2,38),$this->disturbColor); } } private function writeCheckCodeToImage() { for ($i=0;$i<=$this->codenum;$i++) { $bg_color = imagecolorallocate ($this->checkimage, rand(0,255), rand(0,128), rand(0,255)); $x = floor($this->width/$this->codenum)*$i; $y = rand(0,$this->height-15); imagechar ($this->checkimage, rand(5,8), $x, $y, $this->checkcode[$i], $bg_color); } } function __destruct() { unset($this->width,$this->height,$this->codenum); } } ?>
Contains file imgcode.php
<?php session_start(); require_once('CreateImg.class.php'); $image = new ValidationCode('80','20','4'); //图片长度、宽度、字符个数 $image->outImg(); $_SESSION['validationcode'] = $image->checkcode; //存贮验证码到 $_SESSION 中 ?>
Front-end file demo.php
?php session_start(); $test = $_POST['test']; $test = strtoupper(trim($test)); $submit = $_POST['submit']; if(isset($submit)){ if($test==$_SESSION['validationcode']){ echo 'true'; } else { echo 'false'; } } ?> <html> <head> <title>Image</title> <meta http-equiv="content-type" content="text/html;charset=utf-8"> <script language="javascript"> function newgdcode(obj,url) { obj.src = url+ '?nowtime=' + new Date().getTime(); //后面传递一个随机参数,否则在IE7和火狐下,不刷新图片 } </script> <body> <img src="imgcode.php" alt="看不清楚,换一张" align="absmiddle" style="cursor: pointer;" onclick="javascript:newgdcode(this,this.src);" /> <form method="POST" name="form1" action="image.php"> <input type="text" name="test"> <br /> <input type="submit" name="submit" value="提交"> </form> </body> </head> </html>
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