本文实例讲述了PHP生成图片验证码功能。分享给大家供大家参考，具体如下：

只是简单的用随机函数实现了图片的生成，没有对验证的整个流程做介绍。

代码如下：

<?php/** * Created by JetBrains PhpStorm. * User: lee * To change this template use File | Settings | File Templates. */header("content-type:image/png");$validateLength=4;$strToDraw="";$chars=[ "0","1","2","3","4", "5","6","7","8","9", "a","b","c","d","e","f","g", "h","i","j","k","l","m","n", "o","p","q","r","s","t", "u","v","w","x","y","z", "A","B","C","D","E","F","G", "H","I","J","K","L","M","N", "O","P","Q","R","S","T", "U","V","W","X","Y","Z"];$imgW=80;$imgH=25;$imgRes=imagecreate($imgW,$imgH);$imgColor=imagecolorallocate($imgRes,255,255,100);$color=imagecolorallocate($imgRes,0,0,0);for($i=0;$i<$validateLength;$i++){ $rand=rand(1,58); $strToDraw=$strToDraw." ".$chars[$rand];}imagestring($imgRes,5,0,5,$strToDraw,$color);for($i=0;$i<100;$i++){ imagesetpixel($imgRes,rand(0,$imgW),rand(0,$imgH),$color);}imagepng($imgRes);imagedestroy($imgRes);

运行效果如下：

PS：这里再为大家推荐几款比较实用的图片处理工具供大家参考使用：

在线图片转换BASE64工具：
http://tools.jb51.net/transcoding/img2base64

ICO图标在线生成工具：
http://tools.jb51.net/aideddesign/ico_img

在线Email邮箱图标制作工具：
http://tools.jb51.net/email/emaillogo

在线图片格式转换(jpg/bmp/gif/png)工具：
http://tools.jb51.net/aideddesign/picext

更多关于PHP相关内容感兴趣的读者可查看本站专题：《PHP图形与图片操作技巧汇总》、《PHP基本语法入门教程》、《PHP运算与运算符用法总结》、《php面向对象程序设计入门教程》、《PHP网络编程技巧总结》、《PHP数组(Array)操作技巧大全》、《php字符串(string)用法总结》、《php+mysql数据库操作入门教程》及《php常见数据库操作技巧汇总》

希望本文所述对大家PHP程序设计有所帮助。