PHP generates a simple example of a verification code that can be clicked to refresh, PHP generates a verification code example

PHP generates a simple example of a verification code that can be clicked to refresh, PHP generates a verification code example_PHP tutorial

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Jul 12, 2016 am 08:52 AM

phpVerification code

A simple example of PHP generating a verification code that can be clicked to refresh, an example of php generating a verification code

This article describes an example of PHP generating a verification code that can be clicked to refresh. Share it with everyone for your reference, the details are as follows:

html file:

<html>
 <head>
   <title>验证码</title>
 </head>
  <script type="text/javascript">
    function yanzheng(){
      var im=document.getElementsByTagName("img");
      im[0].src="gd.php&#63;temp="+(new Date().getTime().toString(36));
    }
  </script>
 <body>
  <img  src="/static/imghwm/default1.png"  data-src="gd.php"  class="lazy"/ alt="PHP generates a simple example of a verification code that can be clicked to refresh, PHP generates a verification code example_PHP tutorial" ><a href="#" onclick="yanzheng()">换一张</a>
 </body>
</html>

Verification code file gd.php:

<&#63;php
$im=imagecreate(50,20);
$b=imagecolorallocate($im,0,0,0);
$w=imagecolorallocate($im,255,255,255);
$mask="abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789";
$text="";
for($i=1;$i<=4;$i++){
  $index=rand(0,61);
  $text.=$mask{$index};
}
imagestring($im,3,rand(10,20),rand(0,10),$text,$w);
header("Content-type:image/jpeg");
imagejpeg($im);
&#63;>

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I hope this article will be helpful to everyone in PHP programming.

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