$arr = array(1,2,3,4);$file_data = json_encode($res);$download_filename = '123.json';$http_user_agent = $_SERVER['HTTP_USER_AGENT'];header("Content-Type: application/octet-stream");if (preg_match("/MSIE/", $http_user_agent) ) { header('Content-Disposition: attachment; filename="'.$download_filename.'"');} elseif (preg_match("/Firefox/", $http_user_agent)) { header ('Content-Disposition: attachment; filename*="utf8' . $download_filename . '"' );} else { header('Content-Disposition: attachment; filename="'.$download_filename.'"');}header("Accept-Length: ".strlen($file_data));echo $file_data;试了试，谷歌浏览器、火狐浏览器可直接下载；IE浏览器如果出现如下弹窗：
解决方案：在ie菜单栏的【页面】-->【编码】,选择【自动选择】然后下载试试。360浏览器也出现这种问题，待测。
转载于:https://www.cnblogs.com/gyfluck/p/8320762.html
