我们在实际开发中，会用到短信验证码以及网页验证码，相对来说网页验证码的成本比较低，安全系数也还可以，接下来我们就来做一个网页端的验证码，直接上代码：

首先来说一下文件目录结构：

　　　　|----------phpyanzheng  项目文件夹

　　　　　　|----fonttype 文件夹放字体文件，字体文件一般以　.ttf和.otf结尾

　　　　　　|----1.php  里面放php语言代码

　　　　　　|----index.html  里面放网页布局

1.php

<?php
  header("content-type:image/jpeg");//定义一下代码以jpeg文件来解析
  $width = 120;//定义了图像的宽
  $height = 40;//定义了图像的高
  $element = array("q","w","e","r","t","y","u","i","o","p","l","k","j","h","g","f","d","s","a","z","x",
  "c","v","b","n","m","1","2","3","4","5","6","7","8","9","0","Q","W","E","R","T","Y","U","I","O","P","A"
  ,"S","D","F","G","H","J","K","L","M","N","B","V","C","X","Z");//定义一个显示文本的数组
  $string = "";
  for($i=0;$i<4;$i++){
    $string.=$element[rand(0,count($element)-1)];//随机产生四个文本目标
  }
  $img = imagecreatetruecolor($width, $height);//设置验证区宽高
  $colorBg = imagecolorallocate($img,rand(185,255),rand(185,255),rand(185,255));//产生200-255的随机数
  $colorBorder = imagecolorallocate($img,rand(50,100),rand(50,100),rand(50,100));//边框颜色
  $colorDian = imagecolorallocate($img,rand(0,100),rand(0,100),rand(0,100));//背景小点的颜色
  $colorLine = imagecolorallocate($img,rand(0,255),rand(0,255),rand(0,255));
  $colorString = imagecolorallocate($img,rand(20,80),rand(20,80),rand(20,80));
  imagefill($img, 0, 0, $colorBg);//设置位置和背景颜色
  imagerectangle($img,0,0,$width-1,$height-1,$colorBorder);//画一个边框
  for($i=0;$i<200;$i++){//循环出200个干扰点
    imagesetpixel($img, rand(0, $width-1), rand(0, $height-1), $colorDian);
  }
  for($i=0;$i<round(5);$i++){//循环出5条干扰线
    imageline($img,rand(0,$width/2),rand(0,$height/2),rand($width/2,$width),rand($height/2,$height),$colorLine);
  }
  //imagestring($img, 4, 0, 0,"a5dg", $colorString);
  
  imagettftext($img,25,rand(5, 15),rand(0,40),39,$colorString,"fonttype/PrincetownStd.otf",$string);
  //    图像名称  字体大小 倾斜角度 起始位置X轴 起始位置Y轴 颜色 字体位置 显示的内容
  imagejpeg($img);//输出图像
?>

index.html

<!DOCTYPE html>
<html>
  <head>
    <meta charset="UTF-8">
    <title>孙三峰--验证码</title>
    <script type="text/javascript" src="js/jquery-1.1.0.js" ></script>
  </head>
  <body>
    <!--注意：原文中对应的ip地址是自己电脑端ip，如果不能正常运行，请修改ip-->
    <p>
      <label class="lbright">验证码：</label> 
      <span> 
        <input type="text" name="validcode" style="width:70px; vertical-align:middle;" id="validcode"/> 
        <img id="codePic" src="http://192.168.1.113:8601/PHP/phpyanzheng/1.php" width="120" height="40"/>          
      </span>         
      <span id="codePic" onclick="getPic();">看不清楚，换一张</span> <!---->
    </p>     
  </body>
  <script type="text/javascript"> 
     function getPic(){ 
         $("#codePic").attr("src","http://192.168.1.113:8601/PHP/phpyanzheng/1.php?flag="+Math.random()); <!--局部刷新--> 
     }; 
  </script>
</html>

以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持网页设计。