php 设计经典类验证码

最新推荐文章于 2021-03-10 03:16:13 发布

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#设计经典验证码 #php

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本文介绍了一个PHP验证码生成类，详细展示了如何创建包含随机字符的图片验证码，并实现客户端与服务器端的验证码比对验证过程。

1.该类主要对输出图片、图片的背景设置、随机选出不同的颜色点、随机选出不同的数字等

<?php //验证类 validationcode.class.php

class ValidationCode {
private $width;
private $height;
private $codeNum;
private $image; //图像资源
private $disturbColorNum;
private $checkCode;

function __construct($width=80, $height=20, $codeNum=4){
$this->width=$width;
$this->height=$height;
$this->codeNum=$codeNum;
$this->checkCode=$this->createCheckCode();
$number=floor($width*$height/15);

if($number > 240-$codeNum){
$this->disturbColorNum= 240-$codeNum;
}else{
$this->disturbColorNum=$number;
}

}
//通过访问该方法向浏览器中输出图像
function showImage($fontFace=""){
//第一步：创建图像背景
$this->createImage();
//第二步：设置干扰元素
$this->setDisturbColor();
//第三步：向图像中随机画出文本
$this->outputText($fontFace);
//第四步：输出图像
$this->outputImage();
}

//通过调用该方法获取随机创建的验证码字符串
function getCheckCode(){
return $this->checkCode;
}

private function createImage(){
//创建图像资源
$this->image=imagecreatetruecolor($this->width, $this->height);
//随机背景色
$backColor=imagecolorallocate($this->image, rand(225, 255), rand(225,255), rand(225, 255));
//为背景添充颜色
imagefill($this->image, 0, 0, $backColor);
//设置边框颜色
$border=imagecolorallocate($this->image, 0, 0, 0);
//画出矩形边框
imagerectangle($this->image, 0, 0, $this->width-1, $this->height-1, $border);
}

private function setDisturbColor(){
for($i=0; $i<$this->disturbColorNum; $i++){
$color=imagecolorallocate($this->image, rand(0, 255), rand(0, 255), rand(0, 255));
imagesetpixel($this->image, rand(1, $this->width-2), rand(1, $this->height-2), $color);
}

for($i=0; $i<10; $i++){
$color=imagecolorallocate($this->image, rand(200, 255), rand(200, 255), rand(200, 255));
imagearc($this->image, rand(-10, $this->width), rand(-10, $this->height), rand(30, 300), rand(20, 200), 55, 44, $color);
}
}

private function createCheckCode(){
$code="23456789abcdefghijkmnpqrstuvwxyzABCDEFGHIJKMNPQRSTUVWXYZ";
$string='';
for($i=0; $i < $this->codeNum; $i++){
$char=$code{rand(0, strlen($code)-1)};
$string.=$char;
}

return $string;
}

private function outputText($fontFace=""){
for($i=0; $i<$this->codeNum; $i++){
$fontcolor=imagecolorallocate($this->image, rand(0, 128), rand(0, 128), rand(0, 128));
if($fontFace==""){
$fontsize=rand(3, 5);
$x=floor($this->width/$this->codeNum)*$i+3;
$y=rand(0, $this->height-15);
imagechar($this->image,$fontsize, $x, $y, $this->checkCode{$i},$fontcolor);
}else{
$fontsize=rand(12, 16);
$x=floor(($this->width-8)/$this->codeNum)*$i+8;
$y=rand($fontSize+5, $this->height);
imagettftext($this->image,$fontsize,rand(-30, 30),$x,$y ,$fontcolor, $fontFace, $this->checkCode{$i});
}
}
}

private function outputImage() {
if(imagetypes() & IMG_GIF){
header("Content-Type:image/gif");
imagepng($this->image);
}else if(imagetypes() & IMG_JPG){
header("Content-Type:image/jpeg");
imagepng($this->image);
}else if(imagetypes() & IMG_PNG){
header("Content-Type:image/png");
imagepng($this->image);
}else if(imagetypes() & IMG_WBMP){
header("Content-Type:image/vnd.wap.wbmp");
imagepng($this->image);
}else{
die("PHP不支持图像创建");
}
}

function __destruct(){
imagedestroy($this->image);
}
}

2作用：

<?php //验证码图片输出页面

session_start();
echo $_POST["code"]."<br>";//可以注释掉
echo $_SESSION["code"]."<br>";//可以注释掉

if(strtoupper($_POST["code"])==strtoupper($_SESSION["code"])){ //验证码比较对错
echo "ok";
}else{
echo "error";
}
?>
<body>
<form action="login.php" method="post">
user:<input type="text" name="usenrame"><br>
pass:<input type="passowrd" name="pass"><br>

code: <input type="text" name="code" onkeyup="if(this.value!=this.value.toUpperCase()) this.value=this.value.toUpperCase()"> <img src="code.php" onclick="this.src='code.php?'+Math.random()"><br> //code.php？问号把不同的值传到同一个页面

<input type="submit" name="sub" value="login"><br>
</form>
</body>

3.代码重利用可以在此修改

<?php
session_start();
include "validationcode.class.php";

$code=new ValidationCode(80, 20, 4);

$code->showImage(); //输出到页面中供注册或登录使用

$_SESSION["code"]=$code->getCheckCode(); //将验证码保存到服务器中

?>