问题:

The JavaScript example to list files of Google Drive uses gapi.client.drive.files.list(). When trying to use this method I get the error "Cannot read property 'files' of undefined".

The issue and a workaround are already described under Google Drive API javascript

Is the documentation under https://developers.google.com/drive/v2/reference/files/list#try-it incorrect? Or is there a way to use the API as described.

回答1:

The JavaScript example is correct, but you have to make sure that you only use gapi.client.drive.files (and the other Drive-specific resources) when the Drive library is loaded, i.e. after:

gapi.client.load('drive', 'v2', callback);

回答2:

If it works fine after writing gapi.client.load('drive', 'v2', callback), then all good. In my case it does not work so I wrote below code.

gapi.load('client', function () {
                gapi.client.load('drive', 'v2', function () {
                    var file = gapi.client.drive.files.get({ 'fileId': fileId });
                    file.execute(function (resp) {
                        //Write you code with resp variable
                    });

                });
            });