php生成图片验证码功能示例都有什么?

php生成图片验证码功能示例都有什么?

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:

php生成图片验证码功能示例都有什么?

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

希望本文所述对大家PHP程序设计有所帮助。