Copying folders and Subfolders with files using Promises WinJS

Question

Hi,
I have app written in WinJS.
I want to copy a particular folder along with its subfolders and their files. I am so far successful with copying folders. Below is the code for the same.
app.CopyFolder = function (folder, destFolder) {
var replace = Windows.Storage.CreationCollisionOption.replaceExisting;
//console.log("create folder: " + folder.name);
return destFolder.createFolderAsync(folder.name, replace).then(function (newdest) {
return app.CopySubFolders(folder, newdest);
app.CopySubFolders=function(folder, destFolder) {
return folder.getFoldersAsync().then(function (folderlist) {
return WinJS.Promise.join(folderlist.map(function (folder) {
return app.CopyFolder(folder, destFolder);
Now after I have copied all the folders I need to copy their respective files. The problem is I am stuck,I get the files copied but I want to proceed ahead after all the files are written to their respective folders. Below is the code for the same.
app.copyAllFiles = function (fileList, destStorFolder) {
console.log('copyFiles Start...');
var promises = [];
var fileCopied = 0;
var collideOpt = Windows.Storage.CreationCollisionOption.replaceExisting;
return WinJS.Promise.join(fileList.map(function (file) {
return app.copySingleFile(file, destStorFolder);
app.copySingleFile = function (fileObject, destFolder) {
var promises = [];
var fileCopied = 0;
var path = destFolder.path + "\\" + fileObject.folderName;
var collideOpt = Windows.Storage.CreationCollisionOption.replaceExisting;
return Windows.Storage.StorageFolder.getFolderFromPathAsync(path).done(function (folderObjectOfLocalFolder) {
return fileObject.fileObject.copyAsync(folderObjectOfLocalFolder, fileObject.fileName, collideOpt).then(function (fileObject) {
console.log("copied single file:" + fileObject.name);
The problem is when i run the folder copy code and apply breakpoint for the success call back of 
CopySubFolders(source,destination).done(/*my breakpoint*/)
The folders are created.
But when I try to breakpoint for my copyAllFiles,the files are created only when i pass the success call back.
Can anyone tell me what am i doing wrong? How can I proceed ahead only when all the files are written successfully.
Regards,
Ninad 

Answer 1

Hi,
I tried the above solution but what i want is that the action of copying folders and subfolders along with the files should be done with promises and that promise should return only when all folders,sunfolders and their files have been copied. I want to
do it in this way because I want to perform certain second action only when all things are copied.
If I do it the as per the link the function runs in the background and my second action proceed aheads and may cause error if it finds some folder or file missing.
So I came up with following above code,first copy folders then copy. The copy folder works as expected but the files are getting copied only when the file copying code enters the success call back.
Can you please shed light on my code where I am going wrong.
Or is it ok to proceed ahead with the solution you mentioned at the link cause I dont want any runtime crashes.
Regards,
Ninad