php.ini session.save_path = "C:/temp" 把sessin保存在c:/temp
代码：
test.php
PHP code:
<form method="POST" action="http://192.168.1.11/test/test1.php">
<img src="http://192.168.1.11/test/rand.php">
<input type="submit" value="send">
</form>
test1.php
PHP code:
<?php
session_start();
$a=$_SESSION['indexLoginRand'];
echo $a;
if(empty($a)){
echo 'empty';
}
?>
rand.php
PHP code:
<?php
header("Content-type: image/PNG");
session_start();//将随机数存入session中
$_SESSION['indexLoginRand']="";
$im = imagecreate(35,15); //制定图片大小
$black = ImageColorAllocate($im, 0,0,0); //设定颜色
$white = ImageColorAllocate($im, 255,255,255);
imagefill($im,0,0,$white); //区域填充
$authnum = rand(1000,9999);
//将四位整数验证码绘入图片
$_SESSION['indexLoginRand']=$authnum;
imagestring($im, 5, 0, -1, $authnum, $black);
for($i=0;$i<100;$i++) //加入干扰象素
{
$randcolor = ImageColorallocate($im,rand(0,255),rand(0,255),rand(0,255));
imagese
