WriteTextAsync crashes Modern App

Question

Hello,

I have the following code (run from application activated event handler, using presumably UI dispatcher). CreateFileAsync creates the text file but WriteTextAsync crashes. Is this a bug in WinRT libraries?

First-chance exception at 0x00007FFEF60943C8 (KernelBase.dll) in MyApp.exe: 0x40080201: WinRT originate error (parameters: 0x000000008000000B, 0x0000000000000040, 0x000000DE39F6F1E0).

auto t = task<StorageFile^>(KnownFolders::DocumentsLibrary->CreateFileAsync("myfile.txt", CreationCollisionOption::OpenIfExists)).then([&](StorageFile^ file)
			{
				FileIO::WriteTextAsync(file, "Hello");

				return file;
			});

Answer 1

Hi,

I cannot reproduce your problem. When I create a file and then use WriteTextAsync method write text to the file. Everything is very well. And I do not know what you meaning about"run from application activated event handler, using presumably UI dispatcher",Please upload a reproduce sample to OneDrive so that we can test it.

I create a project like below:

MainPage::MainPage()
{
	InitializeComponent();
	auto t = create_task(KnownFolders::DocumentsLibrary->CreateFileAsync("myfile.txt", CreationCollisionOption::OpenIfExists)).then([&](StorageFile^ file)
	{
		FileIO::WriteTextAsync(file, "Hello");

		return file;
	});


}

Best Wishes!

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