将所有csv文件一次导出到内存和zip中

Question

我有一个导出功能，一个csv文件包含每个调查的所有答案。我需要一个函数将所有调查的所有答案（每个csv文件一个调查）导出到menory中并在下载到计算机之前压缩它

不将所有csv文件保存到服务器或本地存储中，我需要将其存储到内存中并在下载到计算机之前将其压缩

我使用过这段代码：

function exportAllAnswer() {
    allTokenId = getAllTokenId();

    foreach(allTokend as $key->$value) {
        exportAnswer($value->id, false);
    }
    $path = 'exportAllCsv';

    // we deliver a zip file
    header("Content-Type: archive/zip");

    // filename for the browser to save the zip file
    header("Content-Disposition: attachment; filename=allCsvs.zip");

    // get a tmp name for the .zip
    $tmp_zip = tempnam ("tmp", "tempname") . ".zip";

    //change directory so the zip file doesnt have a tree structure in it.
    chdir($path);
    // zip the stuff (dir and all in there) into the tmp_zip file
    exec('zip '.$tmp_zip.' *');

    // deliver the zip file
    $fp = fopen("$tmp_zip","r");
    echo fpassthru($fp);

    // clean up the tmp zip file
    unlink($tmp_zip);

    // delete folder csv
    rmdir($path);
}