<?php
session_start();
Header("Content-type: image/gif");
//这里是更改图像的宽高
$im = imagecreate(400,30);
$black = ImageColorAllocate($im, 0,0,0);
$white = ImageColorAllocate($im, 255,255,255);
$num = intval(sprintf("%4d", mt_rand(1, 9999)));
ImageTTFText($im, 20, 0, 10, 20, $white, "./simhei.ttf", $num);
$_SESSION['check_code'] = $num;
//setcookie('num',$num);
ImageGif($im);
?>
还用到 同目录下 simhei.ttf 文件,
