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?temp="+(new Date().getTime().toString(36));
}
</script>
<body>
<img src="gd.php"/><a href="#" onclick="yanzheng()">换一张</a>
</body>
</html>
Verification code file gd.php:
<?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);
?>
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I hope this article will be helpful to everyone in PHP programming.
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