<?php
require_once?'string.func.php';
//通過GD庫做驗證碼
function?varifyImage($sess_name="varify",$type=1,$length=4,$pixel=0,$line=0){
????session_start();
????$width=80;
????$height=28;
????$image=imagecreatetruecolor($width,?$height);//創建畫布
????$white=imagecolorallocate($image,?255,?255,?255);//畫布顏色，白色
????$black=imagecolorallocate($image,?0,?0,?0);//畫筆顏色，黑色
????imagefilledrectangle($image,1,1,$width-2,$height-2,?$white);//用填充矩陣填充畫布
????$chars=buildRandomString($type,$length);//string.func.php中產生隨機字符串的函數
????$_SESSION[$sess_name]=$chars;//用于比對用戶輸入是否正確
????$fontfile="../fonts/SIMYOU.TTF";//字體
????for?($i=0;$i?<?$length;?$i++)?{?//每次產生一個驗證碼字符
????????$size=mt_rand(14,18);
????????$angle=mt_rand(-15,15);
????????$x=5+$i*$size;
????????$y=mt_rand(20,26);
????????$color=imagecolorallocate($image,mt_rand(50,90),?mt_rand(80,200),?mt_rand(90,180));
????????$text=substr($chars,$i,1);//從產生的驗證碼中按順序取一位
????????//以上產生隨機的字符大小、角度、橫坐標、縱坐標、顏色
????????imagettftext($image,?$size,?$angle,?$x,?$y,?$color,?$fontfile,?$text);
????}???
????if?($pixel)?{???//加干擾點
????????$color?=?imagecolorallocate?(?$image,?mt_rand?(?0,?255?),?mt_rand?(?0,?255?),?mt_rand?(?0,?255?)?);
????????for($i?=?0;?$i?<?$pixel;?$i?++)?{
????????????imagesetpixel?(?$image,?mt_rand(?0,?$width-1),?mt_rand(?0,?$height-1),?$black);
????????}
????}???
????if?($line)?{????//加干擾線?
????????for($i?=?0;$i<$line;?$i?++)?{
????????????$color?=?imagecolorallocate($image,mt_rand(0,255?),mt_rand(0,255?),mt_rand(0,?255));
????????????imageline($image,mt_rand(0,?$width-1),?mt_rand?(?0,?$height-1),?mt_rand?(?0,?$width-1),?mt_rand?(?0,?$height-1),?$color?);
????????}
????}
????header("content_type:image/gif");//告訴瀏覽器要顯示什么類型的圖片
????imagegif($image);//顯示畫布
????imagedestroy($image);//銷毀畫布
}
varifyImage();
?>

代碼是照著老師打的(? _ ?)