Windows 8 Metro App File Share Access

Question

I am developing a Windows 8 Metro app, and we intend to deploy it to only a few tablets within our company. It\'s not meant for the Windows Store.

We need the app to

Answer 1

Below is the code that manages to write a file to a network share from WinRT device (Microsoft Surface RT) running Windows 8.1 RT. The essential bits are that:

• share is accessed using a UNC path
• share is public
• application manifest mentions the file type that is written
• application has the proper capabilities

The basic mechanism is described here: http://msdn.microsoft.com/en-US/library/windows/apps/hh967755.aspx

As a bonus, this shows how to capture output to standard output in a WinRT application.

The code:

#include "App.xaml.h"
#include "MainPage.xaml.h"
#include 

using namespace TestApp;

using namespace Platform;
using namespace Windows::UI::Xaml::Navigation;
using namespace Concurrency;

// Anything that is written to standard output in this function will be saved to a file on a network share
int MAIN(int argc, char** argv)
{
    printf("This is log output that is saved to a file on a network share!\n");
    return 0;
}

static char buffer[1024*1024];

Windows::Foundation::IAsyncOperation^ MainPage::RunAsync()
{
    return create_async([this]()->int {
        return MAIN(1, NULL);
    });
}

using namespace concurrency;
using namespace Platform;
using namespace Windows::Storage;
using namespace Windows::System;

void MainPage::Run()
{
    //capture stdout in buffer
    setvbuf(stdout, buffer, _IOFBF, sizeof(buffer));

    task testTask(RunAsync());

    testTask.then([this](int test_result)
    {
        size_t origsize = strlen(buffer) + 1;
        wchar_t* wcstring = new wchar_t[sizeof(buffer)* sizeof(wchar_t)];

        size_t  converted_chars = 0;
        mbstowcs_s(&converted_chars, wcstring, origsize, buffer, _TRUNCATE);
        String^ contents = ref new Platform::String(wcstring);
        delete [] wcstring;

        Platform::String^ Filename = "log_file.txt";
        Platform::String^ FolderName = "\\\\MY-SHARE\\shared-folder";

        create_task(Windows::Storage::StorageFolder::GetFolderFromPathAsync(FolderName)).then([this, Filename, contents](StorageFolder^ folder)
        {
            create_task(folder->CreateFileAsync(Filename, CreationCollisionOption::ReplaceExisting)).then([this, contents](StorageFile^ file)
            {
                create_task(FileIO::WriteTextAsync(file, contents)).then([this, file, contents](task task)
                {
                    try
                    {
                        task.get();
                        OutputBox->Text = ref new Platform::String(L"File written successfully!");
                    }
                    catch (COMException^ ex)
                    {
                        OutputBox->Text = ref new Platform::String(L"Error writing file!");
                    }
                });
            });
        });
    });
}

MainPage::MainPage()
{
    InitializeComponent();
    Run();
}

The manifest:

  
  
    TestApp
    Someone
    Assets\StoreLogo.png
    TestApp
  
  
    6.3
    6.3
  
  
    
  
  
    
      
        
          
            
          
        
        
      
      
        
          
            Text file
            
              .txt