1.在浏览器输出提供下载

    $csv_data = \'\';

    /** 标题 */
    $nums = count($title_arr);
    for ($i = 0; $i < $nums - 1; ++$i) {
        $csv_data .= \'\"\' . $title_arr[$i] . \'\",\';
    }

    if ($nums > 0) {
     $csv_data .= \'\"\' . $title_arr[$nums - 1] . \"\\\"\\r\\n\";
    }

    foreach ($data as $k => $row) {
        for ($i = 0; $i < $nums - 1; ++$i) {
            $row[$i] = str_replace(\"\\\"\", \"\\\"\\\"\", $row[$i]);
            $csv_data .= \'\"\' . $row[$i] . \'\",\';
        }
        $csv_data .= \'\"\' . $row[$nums - 1] . \"\\\"\\r\\n\";
        unset($data[$k]);
    }

    $csv_data = mb_convert_encoding($csv_data, \"cp936\", \"UTF-8\");

    $file_name = empty($file_name) ? date(\'Y-m-d-H-i-s\', time()) : $file_name;

    if (strpos($_SERVER[\'HTTP_USER_AGENT\'], \"MSIE\")) { // 解决IE浏览器输出中文名乱码的bug
     $file_name = urlencode($file_name);
     $file_name = str_replace(\'+\', \'%20\', $file_name);
    }

    $file_name = $file_name . \'.csv\';
    header(\"Content-type:text/csv;\");
    header(\"Content-Disposition:attachment;filename=\" . $file_name);
    header(\'Cache-Control:must-revalidate,post-check=0,pre-check=0\');
    header(\'Expires:0\');
    header(\'Pragma:public\');
    echo $csv_data;
}