$_SESSION输出有关问题
$_SESSION输出问题
生成验证码时候生成随机4个数，放在数组$_SESSION['code']里面，验证码图片
，然后我紧跟在这条代码后面，添加了一条echo $_SESSION['code']，但是显示出来的和验证码图片不一致，比生成的验证码图片要慢一拍，也就是输出的验证码是刷新前的验证码图片上的数字，求大神指点
------解决思路----------------------
表单产生时的执行顺序
echo '';
echo $_SESSION['code']; 要加载到浏览器才会执行
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