Object reference not set to an instance Office 365 api - asp.net-mvc

Question

I am trying to pull a list of files from OneDrive to a list and display it to a view with a MVC application. This is my first go at it so I apologize if I am missing something obvious. I am getting an object reference not set to an instance of an object error. here is my code
public async Task<ActionResult> GetOneDriveFiles()
{
List<OneDriveFiles> myFilesList = new List<OneDriveFiles>();
try
{
var fileResults = await _spFilesClient.Files.Take(10).ExecuteAsync();
var files = fileResults.CurrentPage.OfType<Microsoft.Office365.SharePoint.File>().OrderBy(e => e.Name);
foreach (File file in files)
{
OneDriveFiles myFile = new OneDriveFiles();
myFile.Id = file.Id;
myFile.Name = file.Name;
myFile.Url = file.Url;
myFile.Size = file.Size;
myFile.TimeLastModified = file.TimeLastModified;
myFilesList.Add(myFile);
}
}
catch (RedirectRequiredException redir2)
{
return Redirect(redir2.RedirectUri.ToString());
}
return View(myFilesList);
}
here is the error code:
Exception Details: System.NullReferenceException: Object reference not set to an instance of an object.
Source Error:
An unhandled exception was generated during the execution of the current web request. Information regarding the origin and location of the exception can be identified using the exception stack trace below.
Stack Trace:
[NullReferenceException: Object reference not set to an instance of an object.]
O365APIURSAITO.Controllers.<GetOneDriveFiles>d__14.MoveNext() +110
System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task) +93
System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task) +52
System.Web.Mvc.Async.TaskAsyncActionDescriptor.EndExecute(IAsyncResult asyncResult) +84
System.Web.Mvc.Async.<>c__DisplayClass37.<BeginInvokeAsynchronousActionMethod>b__36(IAsyncResult asyncResult) +17
System.Web.Mvc.Async.WrappedAsyncResult`1.CallEndDelegate(IAsyncResult asyncResult) +10
System.Web.Mvc.Async.WrappedAsyncResultBase`1.End() +49
System.Web.Mvc.Async.AsyncControllerActionInvoker.EndInvokeActionMethod(IAsyncResult asyncResult) +32
System.Web.Mvc.Async.AsyncInvocationWithFilters.<InvokeActionMethodFilterAsynchronouslyRecursive>b__3d() +50
System.Web.Mvc.Async.<>c__DisplayClass46.<InvokeActionMethodFilterAsynchronouslyRecursive>b__3f() +225
System.Web.Mvc.Async.<>c__DisplayClass33.<BeginInvokeActionMethodWithFilters>b__32(IAsyncResult asyncResult) +10
System.Web.Mvc.Async.WrappedAsyncResult`1.CallEndDelegate(IAsyncResult asyncResult) +10
System.Web.Mvc.Async.WrappedAsyncResultBase`1.End() +49
System.Web.Mvc.Async.AsyncControllerActionInvoker.EndInvokeActionMethodWithFilters(IAsyncResult asyncResult) +34
System.Web.Mvc.Async.<>c__DisplayClass2b.<BeginInvokeAction>b__1c() +26
System.Web.Mvc.Async.<>c__DisplayClass21.<BeginInvokeAction>b__1e(IAsyncResult asyncResult) +100
System.Web.Mvc.Async.WrappedAsyncResult`1.CallEndDelegate(IAsyncResult asyncResult) +10
System.Web.Mvc.Async.WrappedAsyncResultBase`1.End() +49
System.Web.Mvc.Async.AsyncControllerActionInvoker.EndInvokeAction(IAsyncResult asyncResult) +27
System.Web.Mvc.Controller.<BeginExecuteCore>b__1d(IAsyncResult asyncResult, ExecuteCoreState innerState) +13
System.Web.Mvc.Async.WrappedAsyncVoid`1.CallEndDelegate(IAsyncResult asyncResult) +36
System.Web.Mvc.Async.WrappedAsyncResultBase`1.End() +54
System.Web.Mvc.Controller.EndExecuteCore(IAsyncResult asyncResult) +39
System.Web.Mvc.Controller.<BeginExecute>b__15(IAsyncResult asyncResult, Controller controller) +12
System.Web.Mvc.Async.WrappedAsyncVoid`1.CallEndDelegate(IAsyncResult asyncResult) +28
System.Web.Mvc.Async.WrappedAsyncResultBase`1.End() +54
System.Web.Mvc.Controller.EndExecute(IAsyncResult asyncResult) +29
System.Web.Mvc.Controller.System.Web.Mvc.Async.IAsyncController.EndExecute(IAsyncResult asyncResult) +10
System.Web.Mvc.MvcHandler.<BeginProcessRequest>b__5(IAsyncResult asyncResult, ProcessRequestState innerState) +21
System.Web.Mvc.Async.WrappedAsyncVoid`1.CallEndDelegate(IAsyncResult asyncResult) +36
System.Web.Mvc.Async.WrappedAsyncResultBase`1.End() +54
System.Web.Mvc.MvcHandler.EndProcessRequest(IAsyncResult asyncResult) +31
System.Web.Mvc.MvcHandler.System.Web.IHttpAsyncHandler.EndProcessRequest(IAsyncResult result) +9
System.Web.CallHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute() +9651188
System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously) +155

Answer 1

My issue was I forgot to ensure the client was created. To do this right after the opening bracket for the try statement put:
public async Task<ActionResult> GetOneDriveFiles()
{
List<OneDriveModel> oneDriveFiles = new List<OneDriveModel>();
try
{
await MyFilesApiSample.EnsureClientCreated();
var allMyFiles = await MyFilesApiSample.GetMyFiles();
foreach (var item in allMyFiles)
{
OneDriveModel newFile = new OneDriveModel();
newFile.Name = item.Name;
newFile.Url = item.Url;
newFile.Size = item.Size;
newFile.LastModified = item.TimeLastModified;
oneDriveFiles.Add(newFile);
}
}
catch (RedirectRequiredException ex)
{
return Redirect(ex.RedirectUri.ToString());
}
return View(oneDriveFiles);
}