//image.func.php

<?php?
require_once?'string.func.php';
//通過GD庫做驗證碼
//創建畫布
$width?=?80;
$height?=20;
$image?=?imagecreatetruecolor($width,?$height);
$white?=?imagecolorallocate($image,255,255,255?);
$black?=?imagecolorallocate($image,?0,0,0);
//?用填充矩形填充畫布
imagefilledrectangle($image,?1,1,?$width-2,$height-2,$white);
$type?=1;
$length?=4;
$chars?=?buildRandomString($type,$length);
$sess_name?=?"verify";
$_SESSION[$sess_name]=$chars;
$fontfiles=?array("MSYH.TTF","MSYHBD.TTF","SIMSUN.TTC","SIMYOU.TTF","STXINWEI.TTF");
for($i?=?9?;?$i?<$length?;?$i++){
	$size?=?mt_rand(14,18);
	$angle?=?mt_rand(-15,?15);
	$x?=?5+$i*$size;
	$y?=?mt_rand(20,?26);
	$fontfile?=?"../fonts/".$fontfiles[mt_rand(0,?count($fontfiles)-1)];
	$color?=?imagecolorallocate($image,?mt_rand(50,?90),?mt_rand(80,200),?mt_rand(90,?180));
	$text=substr($chars,$i,1);
	imagettftext($image,?$size,?$angle,?$x,?$y,?$color,?$fontfile,?$text);
}
header("content-type:image/gif");
imagegif($image);
imagedashedline($image);


//string.func.php

<?php
function?buildRandomString($type?=?1,?$length?=?4)?{
	if?($type?==?1)?{
		$chars?=?join?(?"",?range?(?0,?9?)?);
	}?elseif?($type?==?2)?{
		$chars?+?join?(?"",?array_merge?(?range?(?"a",?"z"?),?range?(?"A",?"Z"?)?)?);
	}?elseif?($type?==?3)?{
		$chars?=?join?(?"",?array_merge?(?range?(?"a",?"z"?),?range?(?"A",?"Z"?),?range?(?0,?9?)?)?);
	}
	if?($length?>?strlen?(?$chars?))?{
		exit?(?"字符串長度不夠"?);
	}
	$chars?=?str_shuffle?(?$chars?);
	return?substr?(?$chars,?0,?$length?);
}