PHP生成圖片驗證碼功能示例，

PHP生成圖片驗證碼功能示例，

本文實例講述了PHP生成圖片驗證碼功能。分享給大家供大家參考，具體如下：

只是簡單的用隨機函數實現了圖片的生成，沒有對驗證的整個流程做介紹。

代碼如下：

<?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);

運行效果如下：

PS：這裡再為大家推薦幾款比較實用的圖片處理工具供大家參考使用：

在線圖片轉換BASE64工具：
http://tools.jb51.net/transcoding/img2base64

ICO圖標在線生成工具：
http://tools.jb51.net/aideddesign/ico_img

在線Email郵箱圖標制作工具：
http://tools.jb51.net/email/emaillogo

在線圖片格式轉換(jpg/bmp/gif/png)工具：
http://tools.jb51.net/aideddesign/picext

更多關於PHP相關內容感興趣的讀者可查看本站專題：《PHP圖形與圖片操作技巧匯總》、《PHP基本語法入門教程》、《PHP運算與運算符用法總結》、《php面向對象程序設計入門教程》、《PHP網絡編程技巧總結》、《PHP數組(Array)操作技巧大全》、《php字符串(string)用法總結》、《php+mysql數據庫操作入門教程》及《php常見數據庫操作技巧匯總》

希望本文所述對大家PHP程序設計有所幫助。