使用JavaScript下载多个文件

Question

我对此非常新鲜，因此通过反复试验学习。

我有一个JavaScript，到目前为止，它正在授权访问用户Google Drive。它创建了一些文件的数组，我可以访问meta数据以获取每个文件的下载。

function downloadFile() {
            gapi.client.load('drive', 'v2', makeRequest);
        }

        function makeRequest() {
            var request = gapi.client.request({
                    'path': '/drive/v2/files',
                    'method': 'GET',
                    'params': {'q': 'title contains "This"'} // retrieve all files with a filename that begins with the word "This"
                });
            request.execute(function(resp) {
                for (i = 0; i < resp.items.length; i++) {
                    var dlUrl = resp.items[i].downloadUrl; //this is the url extracted from the request
                    var finalDlUrl = dlUrl.split("&gd=true");//the url needs to be trimmed so the last 8 characters are ignored in order to work
                   window.location.assign(finalDlUrl);

                }
            });

如何使脚本循环遍历每个文件数组元素并下载每个元素。我知道要使用" for Loop"，但是触发文件下载的实际方法是什么，因此它们出现在我的浏览器下载文件夹中。

另外，它可能是相关的，使用gapi.client.request({/* etc */})

Answer 1

您可以创建一个iFrame，然后将SRC设置为下载值。您可能需要设置超时...

    function downloadFile() {
        gapi.client.load('drive', 'v2', makeRequest);
    }

    function makeRequest() {
        var request = gapi.client.request({
                'path': '/drive/v2/files',
                'method': 'GET',
                'params': {'q': 'title contains "This"'} // retrieve all files with a filename that begins with the word "This"
        });
        request.execute(function(resp) {
            for (i = 0; i < resp.items.length; i++) {
                var dlUrl = resp.items[i].downloadUrl; //this is the url extracted from the request
                var finalDlUrl = dlUrl.split("&gd=true");//the url needs to be trimmed so the last 8 characters are ignored in order to work
               downloadUrl(finalDlUrl);
            }
        });
    }
    function downloadUrl(url) {
        var iframe = document.createElement("iframe");
        iframe.src = url;
        iframe.style.display = "none";
        document.body.appendChild(iframe);
    }

这是一些可能按顺序下载文件的代码：

    function downloadFile() {
        gapi.client.load('drive', 'v2', makeRequest);
    }
    function makeRequest() {
        var request = gapi.client.request({
                'path': '/drive/v2/files',
                'method': 'GET',
                'params': {'q': 'title contains "This"'}
            });
        request.execute(function(resp) {
            downloadFiles(0, resp.items);
        });
    }
    function downloadFiles(current, list)
    {
        var next = current + 1;
        if(next == list.length) {
            return;
        }
        var dlUrl = resp.items[next].downloadUrl;
        var finalDlUrl = dlUrl.split("&gd=true");
        var iframe = document.createElement("iframe");
        iframe.src = finalDlUrl;
        iframe.style.display = "none";
        document.body.appendChild(iframe);
        iframe.onload = function() {
            downloadFiles(next, list);
        };
    }