<?php
require_once'string.func.php';
//通過GD庫實現驗證碼
function($type=1,$length=4,$pixel=50,$sess_name?=?"verify"){
	

//創建畫布
$width=80;//設定寬度
$height=28;//設定高度
$image=imagecreatetruecolor($width,$height);//設定畫布寬度高度參數
$white=imagecolorallocate($image,255,255,255);//為畫布填充白色
$black=imagecolorallocate($image,0,0,0);//為畫布填充黑色

imagefilledrectangle($image,1,1,$width-2,$height-2,$white);//用矩形填充畫布

$chars=buildRandomString?($type,$length);

$_SESSION[$sess_name]=$chars;
$fontfiles=array("BirchStd.otf");//設定字體
for($i=0;$i<$length;$i++){
????$size=mt_rand(14,18);//設定大小
????$angle=mt_rand(-15,15);//設定角度
????$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);
}

if($pixel){
????for($i=0;$i<$pixel;$i++){
???????imagesetpixel?(?$image,?mt_rand?(?0,?$width?-?1?),?mt_rand?(?0,?$height?-?1?),?$black?);
????}

}

header("content-type:image/gif");
imagegif($image);
imagegif($image);
imagedestroy($image);
}

?>