Detailed explanation of the calling method example of PHP verification code class-PHP Tutorial-php.cn

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Detailed explanation of the calling method example of PHP verification code class

黄舟

Sep 15, 2017 am 09:21 AM

phpExampleDetailed explanation

This article mainly introduces the PHP verification code file and the detailed explanation of the calling method code. Friends in need can refer to the

code as follows:

//验证码类
class ValidateCode {
 private $charset = &#39;abcdefghkmnprstuvwxyzABCDEFGHKMNPRSTUVWXYZ23456789&#39;;//随机因子
 private $code;//验证码
 private $codelen = 4;//验证码长度
 private $width = 130;//宽度
 private $height = 50;//高度
 private $img;//图形资源句柄
 private $font;//指定的字体
 private $fontsize = 20;//指定字体大小
 private $fontcolor;//指定字体颜色
 //构造方法初始化
 public function __construct() {
 $this->font = dirname(__FILE__).&#39;/font/elephant.ttf&#39;;//注意字体路径要写对，否则显示不了图片
 }
 //生成随机码
 private function createCode() {
 $_len = strlen($this->charset)-1;
 for ($i=0;$i<$this->codelen;$i++) {
 $this->code .= $this->charset[mt_rand(0,$_len)];
 }
 }
 //生成背景
 private function createBg() {
 $this->img = imagecreatetruecolor($this->width, $this->height);
 $color = imagecolorallocate($this->img, mt_rand(157,255), mt_rand(157,255), mt_rand(157,255));
 imagefilledrectangle($this->img,0,$this->height,$this->width,0,$color);
 }
 //生成文字
 private function createFont() {
 $_x = $this->width / $this->codelen;
 for ($i=0;$i<$this->codelen;$i++) {
 $this->fontcolor = imagecolorallocate($this->img,mt_rand(0,156),mt_rand(0,156),mt_rand(0,156));
 imagettftext($this->img,$this->fontsize,mt_rand(-30,30),$_x*$i+mt_rand(1,5),$this->height / 1.4,$this->fontcolor,$this->font,$this->code[$i]);
 }
 }
 //生成线条、雪花
 private function createLine() {
 //线条
 for ($i=0;$i<6;$i++) {
 $color = imagecolorallocate($this->img,mt_rand(0,156),mt_rand(0,156),mt_rand(0,156));
 imageline($this->img,mt_rand(0,$this->width),mt_rand(0,$this->height),mt_rand(0,$this->width),mt_rand(0,$this->height),$color);
 }
 //雪花
 for ($i=0;$i<100;$i++) {
 $color = imagecolorallocate($this->img,mt_rand(200,255),mt_rand(200,255),mt_rand(200,255));
 imagestring($this->img,mt_rand(1,5),mt_rand(0,$this->width),mt_rand(0,$this->height),&#39;*&#39;,$color);
 }
 }
 //输出
 private function outPut() {
 header(&#39;Content-type:image/png&#39;);
 imagepng($this->img);
 imagedestroy($this->img);
 }
 //对外生成
 public function doimg() {
 $this->createBg();
 $this->createCode();
 $this->createLine();
 $this->createFont();
 $this->outPut();
 }
 //获取验证码
 public function getCode() {
 return strtolower($this->code);
 }
}

Usage:

1. First save the verification code class as a name For the file ValidateCode.class.php;

2. Create a new file named captcha.php to call the class;

captcha.php

3. Referenced to the page, the code is as follows:

4. A complete verification page, the code is as follows:

<?php
session_start();
//在页首先要开启session,
//error_reporting(2047);
session_destroy();
//将session去掉，以每次都能取新的session值;
//用seesion 效果不错，也很方便
?>
<html>
<head>
<title>session 图片验证实例</title>
<style type="text/css">
#login p{
margin-top: 15px;
line-height: 20px;
font-size: 14px;
font-weight: bold;
}
#login img{
cursor:pointer;
}
form{
margin-left:20px;
}
</style>
</head> 
<body>
<form id="login" action="" method="post">
<p>此例为session验证实例</p>
<p>
<span>验证码：</span>
<input type="text" name="validate" value="" size=10> 
<img  src="/static/imghwm/default1.png"  data-src="./captcha.php"  class="lazy"  title="点击刷新"  align="absbottom" onclick="this.src=&#39;captcha.php?&#39;+Math.random();" alt="Detailed explanation of the calling method example of PHP verification code class" ></img>
</p>
<p>
<input type="submit">
</p>
</form>
<?php
//打印上一个session;
//echo "上一个session：<b>".$_SESSION["authnum_session"]."</b><br>";
$validate="";
if(isset($_POST["validate"])){
$validate=$_POST["validate"];
echo "您刚才输入的是：".$_POST["validate"]."<br>状态：";
if($validate!=$_SESSION["authnum_session"]){
//判断session值与用户输入的验证码是否一致;
echo "<font color=red>输入有误</font>"; 
}else{
echo "<font color=green>通过验证</font>"; 
}
} 
?>

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