First published on MSDN on Sep 24, 2014
Here is sample code to download and upload files to OneDrive from Universal Windows Apps.
Complete source code is available
here
Introduction to Universal Windows Apps
Visual Studio template for Universal Windows Apps allows developers to build Windows Store App and Phone App in a single Visual Studio solution. This Visual Studio solution includes three projects, project for design and feature experiences unique to Store App, second project for Phone App and third project for shared code. For more details on Universal Apps template in Visual Studio please click
here
Here is the Visual Studio projects for Universal Windows Apps.
The project ending with .Windows is for Store App, project ending with .WindowsPhone is for Phone App and .Shared is for shared code.
In the Shared Project, use following #defines to write specific code for Phone App or Store App
#if WINDOWS_PHONE_APP
// For Windows Phone App
#elif WINDOWS_APP
// For Windows Store App
#else
// Error
#endif
Introduction to OneDrive
Microsoft OneDrive is cloud-based storage solution for all your applications’ end-users' information, files, and folders. For more details please click
here
.
Use Azure Storage as cloud-based storage solution for all your applications’ files that are common to all end-users. For more details please click
here
.
Steps to create Universal Windows App
-
Open Visual Studio
-
Click on File | New
-
Select Templates | Visual C# | Store Apps | Universal Apps | Hub App as shown
-
Now install NuGet Package for OneDrive
-
Right click on the .Windows project and select Manage NuGet Packages
-
In the search textbox type Live SDK and select package created by Microsoft as shown below
-
Click on Install button for Live SDK
-
Now install the OneDrive (Live SDK) NuGet Package on .WindowsPhone project
-
Right click on the .WindowsPhone project and select Manage NuGet Packages
-
In the search textbox type Live SDK and click on the install button on package created by Microsoft
-
Now lets right code for uploading file to OneDrive
-
Open App.xaml.cs file in the .Shared Project
-
Copy this below upload function
LiveConnectClient liveClient;
private async Task<int> UploadFileToOneDrive()
{
try
{
// create OneDrive auth client
var authClient = new LiveAuthClient();
// ask for both read and write access to the OneDrive
LiveLoginResult result = await authClient.LoginAsync(new string[] { "wl.skydrive", "wl.skydrive_update" });
// if login successful
if (result.Status == LiveConnectSessionStatus.Connected)
{
// create a OneDrive client
liveClient = new LiveConnectClient(result.Session);
// create a local file
StorageFile file = await ApplicationData.Current.LocalFolder.CreateFileAsync("filename", CreationCollisionOption.ReplaceExisting);
// copy some txt to local file
MemoryStream ms = new MemoryStream();
DataContractSerializer serializer = new DataContractSerializer(typeof(string));
serializer.WriteObject(ms, "Hello OneDrive World!!");
using (Stream fileStream = await file.OpenStreamForWriteAsync())
{
ms.Seek(0, SeekOrigin.Begin);
await ms.CopyToAsync(fileStream);
await fileStream.FlushAsync();
}
// create a folder
string folderID = await GetFolderID("folderone");
if (string.IsNullOrEmpty(folderID))
{
// return error
return 0;
}
// upload local file to OneDrive
await liveClient.BackgroundUploadAsync(folderID, file.Name, file, OverwriteOption.Overwrite);
return 1;
}
}
catch
{
}
// return error
return 0;
}
-
Copy this below code to create a folder on OneDrive
public async Task<string> GetFolderID(string folderName)
{
try
{
string queryString = "me/skydrive/files?filter=folders";
// get all folders
LiveOperationResult loResults = await liveClient.GetAsync(queryString);
dynamic folders = loResults.Result;
foreach (dynamic folder in folders.data)
{
if (string.Compare(folder.name, folderName, StringComparison.OrdinalIgnoreCase) == 0)
{
// found our folder
return folder.id;
}
}
// folder not found
// create folder
Dictionary<string, object> folderDetails = new Dictionary<string, object>();
folderDetails.Add("name", folderName);
loResults = await liveClient.PostAsync("me/skydrive", folderDetails);
folders = loResults.Result;
// return folder id
return folders.id;
}
catch
{
return string.Empty;
}
}
-
Now copy this below download function
public async Task<int> DownloadFileFromOneDrive()
{
try
{
string fileID = string.Empty;
// get folder ID
string folderID = await GetFolderID("folderone");
if (string.IsNullOrEmpty(folderID))
{
return 0; // doesnt exists
}
// get list of files in this folder
LiveOperationResult loResults = await liveClient.GetAsync(folderID + "/files");
List<object> folder = loResults.Result["data"] as List<object>;
// search for our file
foreach (object fileDetails in folder)
{
IDictionary<string, object> file = fileDetails as IDictionary<string, object>;
if (string.Compare(file["name"].ToString(), "filename", StringComparison.OrdinalIgnoreCase) == 0)
{
// found our file
fileID = file["id"].ToString();
break;
}
}
if (string.IsNullOrEmpty(fileID))
{
// file doesnt exists
return 0;
}
// create local file
StorageFile localFile = await ApplicationData.Current.LocalFolder.CreateFileAsync("filename_from_onedrive", CreationCollisionOption.ReplaceExisting);
// download file from OneDrive
await liveClient.BackgroundDownloadAsync(fileID + "/content", localFile);
return 1;
}
catch
{
}
return 0;
}
-
Now call these two functions
protected async override void OnLaunched(LaunchActivatedEventArgs e)
{
#if DEBUG
if (System.Diagnostics.Debugger.IsAttached)
{
this.DebugSettings.EnableFrameRateCounter = true;
}
#endif
int r = await UploadFileToOneDrive();
if( r== 1)
{
await DownloadFileFromOneDrive();
}
Frame rootFrame = Window.Current.Content as Frame;
-
Run the Windows Store App
-
Did you get any errors ?
{"Object reference not set to an instance of an object."}
at Microsoft.Live.ResourceHelper.GetString(String name)
at Microsoft.Live.TailoredAuthClient.<AuthenticateAsync>d__0.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
at System.Runtime.CompilerServices.TaskAwaiter`1.GetResult()
at Microsoft.Live.LiveAuthClient.<ExecuteAuthTaskAsync>d__8.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
at System.Runtime.CompilerServices.TaskAwaiter`1.GetResult()
at UniversalAppOneDrive.App.<UploadFileToOneDrive>d__a.MoveNext()
-
This error usually indicates our current Windows Store App is not associated to an App Name in the store
-
To associate our current app with the Store, right click on .Windows project, select Store | Associate App with the Store…
-
Sign in with your developer account and register the app name
-
Now run the Windows Store App again
-
This time Microsoft Account UI will ask end user permission to allow your app to access their OneDrive as shown below
-
-
here
is the complete source code