php实现点击可刷新验证码_php技巧

验证码类文件 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); } } ?>

包含文件 https://www.gxlcms.com/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 
?>

前台文件 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'; 
} 
} 
?> 
 
 
 
 
 
 
 
 
 
 
 
 

以上就是为大家介绍的php点击验证码即可刷新的全部代码，希望对大家的学习有所帮助。