checksubmit检测是否重复提交订单函数

checksubmit检测是否重复提交订单函数

HTML 代码表单里天添加：
  <input type="hidden" name="token" value="{$_W['token']}" />

function checksubmit($var = 'submit', $allowget = false) {
	global $_W, $_GPC;
	if (empty($_GPC[$var])) {
		return FALSE;
	}
	if(defined('IN_SYS')) {
		if ($allowget || (($_W['ispost'] && !empty($_W['token']) && $_W['token'] == $_GPC['token']) && (empty($_SERVER['HTTP_REFERER']) || preg_replace("/https?://([^:/]+).*/i", "\1", $_SERVER['HTTP_REFERER']) == preg_replace("/([^:]+).*/", "\1", $_SERVER['HTTP_HOST'])))) {
			return TRUE;
		}
	} else {
		if(empty($_W['isajax']) && empty($_SESSION['token'][$_GPC['token']])) {
			message('抱歉，表单已经失效请您重新进入提交数据', referer(), 'error');
		} else {
			unset($_SESSION['token'][$_GPC['token']]);
		}
		return TRUE;
	}
	return FALSE;
}