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Windows FolderPicker stopped working after updating to Windows 10.0.18362

I have code that was using the windows FolderPicker. After updating to Windows version 10.0.18362, my use of the FoldePicker has stopped working.
I have attached some code that I used in order to get the access to file is denied result.
using System;
using System.IO;
using Windows.UI.Xaml;
using Windows.UI.Xaml.Controls;
using Windows.Storage.Pickers;
using Windows.Storage;
using Windows.Storage.AccessCache;
namespace FolderPickerTest
{
public sealed partial class MainPage : Page
{
private static string path = #"filepath";
string[] lines;
public MainPage()
{
this.InitializeComponent();
test();
}
public async void test()
{
var folderPicker = new FolderPicker();
folderPicker.SuggestedStartLocation = PickerLocationId.Desktop;
folderPicker.FileTypeFilter.Add("*");
StorageFolder folder = await folderPicker.PickSingleFolderAsync();
if (folder != null)
{
StorageApplicationPermissions.FutureAccessList.AddOrReplace("PickedFolderToken", folder);
}
}
private void open_click(object sender, RoutedEventArgs e)
{
lines = new string[2];
try
{
lines = File.ReadAllLines(path);
}
catch(Exception ex)
{
errorText.Text = ($"Error: {ex.Message.ToString()}");
}
}
}
}
The error message that I am currently getting is:
Access to the path 'filepath' is denied

The problem here is that you are trying to read an arbitrary path using System.IO APIs. In one of the releases this was actually working when you declared the broadFileSystemAccess capability, but this is no longer the case. You now must use the StorageFile APIs to achieve your goal.
If you pick a folder with FolderPicker, you get a StorageFolder instance back. You can call GetFileAsync method on this instance to get a file by name. This is an instance of StorageFile which you can read using FileIO.ReadLinesAsync method.

To explain better the answer of Martin Zikmund, in Win 10 1803 (april 2018), broadFileSystemAccess capability was set automatically to ON in the user Settings.
Starting from Win 10 1809 (October 2018), this System setting is set to OFF by default.
You need to ask the user to explicitly set the setting ON in the Settings app, even by referencing the specific setting page directly.

Download files in Cefsharp to a directory allow user to open

I am working on building a primitive and basic web browser on which my workplace would like to host some internal applications. I"m using cefSharp in a WinForms application written in C#. I've succeeded in building the browser to navigate the application, but I'm having trouble with the download handler. I would like to download files directly to the C:\Users\[username]\Downloads folder (all of our computers are Windows computers) without having to use the dialog.
Reading from Force CEFSharp to download without showing dialog suggests that using showDialog: false should work, but when I apply this, nothing downloads. Likewise, I've made no progress by studying any of the following:
WPF : download files through CefSharp
https://github.com/cefsharp/CefSharp/blob/cd934267c65f494ceb9ee75995cd2a1ca0954543/CefSharp.Example/DownloadHandler.cs
WPF : download files through CefSharp
https://groups.google.com/forum/?nomobile=true#!topic/cefsharp/bS8PhHRlSAc
https://groups.google.com/forum/#!topic/cefsharp/3cMUHSGxPDc
As a bonus, it'd be nice to have the option to open the file, such as in Google Chrome, but this isn't strictly necessary.
The code below runs smoothly and approximates what I am attempting. This example opens to a GitHub Gist. Clicking on the "Download Zip" button on the right opens the dialog to download and save the file.
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Web.Script.Serialization;
using System.Windows.Forms;
using CefSharp;
using CefSharp.WinForms;
using System.IO;
namespace ShinyChrome
{
public partial class ShinyApp : Form
{
public class DownloadHandler : IDownloadHandler
{
public event EventHandler<DownloadItem> OnBeforeDownloadFired;
public event EventHandler<DownloadItem> OnDownloadUpdatedFired;
public void OnBeforeDownload(IBrowser browser, DownloadItem downloadItem, IBeforeDownloadCallback callback)
{
var handler = OnBeforeDownloadFired;
if (handler != null)
{
handler(this, downloadItem);
}
if (!callback.IsDisposed)
{
using (callback)
{
callback.Continue(downloadItem.SuggestedFileName, showDialog: true);
}
}
}
public void OnDownloadUpdated(IBrowser browser, DownloadItem downloadItem, IDownloadItemCallback callback)
{
var handler = OnDownloadUpdatedFired;
if (handler != null)
{
handler(this, downloadItem);
}
}
}
public ShinyApp()
{
InitializeComponent();
}
ChromiumWebBrowser chrome;
private void ShinyApp_Load(object sender, EventArgs e)
{
CefSettings settings = new CefSettings();
Cef.Initialize(settings);
chrome = new ChromiumWebBrowser("https://gist.github.com/nutterb/32992747c1a69aa7a8fdcc2b5347178f");
chrome.DownloadHandler = new DownloadHandler();
this.shinyContainer.Controls.Add(chrome);
}
}
}

On TEK's advice, I replaced the if(!callback.IsDisposed) block in the question with the code below.
if (!callback.IsDisposed)
{
using (callback)
{
callback.Continue(#"C:\Users\" +
System.Security.Principal.WindowsIdentity.GetCurrent().Name. +
#"\Downloads\" +
downloadItem.SuggestedFileName,
showDialog: false);
}
}

Synaptics SDK can't find device

I'm attempting to grab a device handle on the Synaptics Touchpad using the Synaptics SDK, specifically using methods in the SYNCTRLLib.
However, the SYNCTRL method failed to find it, returning -1.
Syn.cs:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using SYNCOMLib;
using SYNCTRLLib;
namespace TP_Test1
{
class Syn
{
SynAPICtrl SynTP_API = new SynAPICtrl();
SynDeviceCtrl SynTP_Dev = new SynDeviceCtrl();
SynPacketCtrl SynTP_Pack = new SynPacketCtrl();
int DeviceHandle;
//Constructor
public Syn ()
{
SynTP_API.Initialize();
SynTP_API.Activate();
//DeviceHandle == -1 ? Can't find device?
DeviceHandle = SynTP_API.FindDevice(new SynConnectionType(), new SynDeviceType(), 0);
//Below line causing Unhandled Exception
SynTP_Dev.Select(DeviceHandle);
SynTP_Dev.Activate();
SynTP_Dev.OnPacket += SynTP_Dev_OnPacket;
}
public void SynTP_Dev_OnPacket()
{
Console.WriteLine(SynTP_Pack.FingerState);
Console.WriteLine(SynTP_Pack.X);
Console.WriteLine(SynTP_Pack.Y);
}
}
}
Program.cs
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using SYNCOMLib;
using SYNCTRLLib;
namespace TP_Test1
{
class Program
{
static void Main(string[] args)
{
Syn mySyn = new Syn();
mySyn.SynTP_Dev_OnPacket();
}
}
}

I see that you are using the C# wrappers for Synaptics SDK. Even though CPP code might be not trivial to you, you might want to take a look at the file Samples/ComTest.cpp. It contains some example logic in order to find devices, more specifically at lines 66-76:
// Find a device, preferentially a TouchPad or Styk.
ISynDevice *pDevice = 0;
long lHandle = -1;
if ((pAPI->FindDevice(SE_ConnectionAny, SE_DeviceTouchPad, &lHandle) &&
pAPI->FindDevice(SE_ConnectionAny, SE_DeviceStyk, &lHandle) &&
pAPI->FindDevice(SE_ConnectionAny, SE_DeviceAny, &lHandle)) ||
pAPI->CreateDevice(lHandle, &pDevice))
{
printf("Unable to find a Synaptics Device.\n");
exit(-1);
}
Also, make sure you have registered the dlls. According to the ReadSynSDK.txt file:
For certain purposes it may be necessary to register the dlls
that are provided with the SDK. This can be done with the windows regsvr32
utility.

How to send array via Bluetooth Low Energy in Windows Desktop APP?

I'm having enormous trouble communicating with my arduino over BLE in my Windows desktop application. I did understand that i have to enable WinRT API in my application to access GATT and to use win 8.1 etc. (I followed this tutorial https://software.intel.com/en-us/articles/using-winrt-apis-from-desktop-applications). I don't understand how to communicate with my device from this point.
So i have this values for the device (adafruit nrf8001):
UART Service UUID: 6E400001-B5A3-F393-E0A9-E50E24DCCA9E
TX Characteristic UUID: 6E400002-B5A3-F393-E0A9-E50E24DCCA9E
RX Characteristic UUID: 6E400003-B5A3-F393-E0A9-E50E24DCCA9E
how do i send a simple array - or easier a simple ASCII value to the device? On iOS and android i find plenty of examples, but not for a windows desktop app ...
would be super happy if someone can help!
phil
edit: i thought this should do the job... but the app crashes on the last point:
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using Windows.Devices.Bluetooth.GenericAttributeProfile;
using Windows.Devices.Enumeration;
using Windows.UI.Xaml;
namespace LucidMobileCCproto
{
public partial class LucidMIControlPanel : Form
{
GattDeviceService service2 = null;
private async void Discover_Click(object sender, EventArgs e)
{
var Services = await Windows.Devices.Enumeration.DeviceInformation.FindAllAsync(GattDeviceService.GetDeviceSelectorFromUuid(new Guid("6E400001-B5A3-F393-E0A9-E50E24DCCA9E")), null);
GattDeviceService Service = await GattDeviceService.FromIdAsync(Services[0].Id);
//Check Service Name
textBox1.Text = "Using service: " + Services[0].Name;
GattReliableWriteTransaction gattTransaction = new GattReliableWriteTransaction(); //Orientation on MSDN Article
GattCharacteristic gattCharacteristic = Service.GetCharacteristics(new Guid("6E400002-B5A3-F393-E0A9-E50E24DCCA9E"))[0];
//Check Characteristic
textBox2.Text = Convert.ToString(gattCharacteristic.CharacteristicProperties);
//initialize Buffer
var writer = new Windows.Storage.Streams.DataWriter();
writer.WriteByte(2);
gattTransaction.WriteValue(gattCharacteristic, writer.DetachBuffer());
//Programm Crashes here
GattCommunicationStatus status = await gattTransaction.CommitAsync();
}
}
The crash: Exception:Thrown: "The attribute cannot be written. (Exception from HRESULT: 0x80650003)" (System.Exception)
A System.Exception was thrown: "The attribute cannot be written. (Exception from HRESULT: 0x80650003)"

wow just took me a few hours to get the solution:
I Just had to add the write option (i deleted the reliable write as well)
private async void Discover_Click(object sender, EventArgs e)
{
var Services = await Windows.Devices.Enumeration.DeviceInformation.FindAllAsync(GattDeviceService.GetDeviceSelectorFromUuid(new Guid("6E400001-B5A3-F393-E0A9-E50E24DCCA9E")));
GattDeviceService Service = await GattDeviceService.FromIdAsync(Services[0].Id);
GattCharacteristic gattCharacteristic = Service.GetCharacteristics(new Guid("6E400002-B5A3-F393-E0A9-E50E24DCCA9E"))[0];
var writer = new DataWriter();
writer.WriteString("#FF00FF");
var res = await gattCharacteristic.WriteValueAsync(writer.DetachBuffer(), GattWriteOption.WriteWithoutResponse);
}

Call a 'host' callback from a 'compiled assembly from source'

I'm compiling code on-the-fly using System.CodeDom.Compiler. Everything inside the compiled source works well, whatever I'm putting inside this source. I know how to call my functions:
o = results.CompiledAssembly.CreateInstance("Foo.Bar");
MethodInfo mi = o.GetType().GetMethod("SayHello");
mi.Invoke(o, null);
But let's say I'm using a WebClient to retrieve a string asynchronously using WebClient.DownloadStringAsync. Or any other context where I want my compiled source to tell to the host "Hey, I got a nice string ready for you." For the example, I've used a WebBrowser. Basically, I know how to deal with each of the two instances: My hosting program and the compiled program, but I want my compiled program to communicate with the host. By the way, I'm not a super-experimented programmer, so no obvious method comes to my mind.
What I've tried:
1 . I don't really need to try it because it would work, but I could use a timer reading a strings stack or tasks queue inside the compiled source, but the purpose of my application is to have +- 60 scripts able to execute ponctual tasks, not continuous background processes, so it wouldn't be efficient on the CPU.
2 . I've passed the handler to the compiled source like if it was in the hosting app:
//In the hosting app
MethodInfo mi2 = o.GetType().GetMethod("attachCallbackToHost");
mi2.Invoke(o2, new object[] { new WebBrowserNavigatedEventHandler (wb_navigated) });
//... And the handler
public static void wb_navigated(object sender, WebBrowserNavigatedEventArgs e)
{
string browserHtmlFromCompiledSource = ((WebBrowser)sender).DocumentText;
MessageBox.Show(browserHtmlFromCompiledSource);
}
// Plain text from the compiled source code
public void attachCallbackToHost(WebBrowserNavigatedEventHandler handlerFromTheHost)
{
wb.Navigated += handlerFromTheHost;
}
And it did nothing.
3 . Maybe I could share a class or variable by passing it to the compiled assembly?
So, the question is either this or the other:
How to watch efficiently for change inside a specific variable or property inside the compiled program?
How to attach a callback to the host?

Ok. I got it: In order to access the host from the compiled source, the only thing required is to add the host assembly to the refered assemblies in the compiler parameters:
compilerParams.ReferencedAssemblies.Add(Assembly.GetExecutingAssembly().Location);
So no need for any special callback or INotifier.
Here's the full code that strictly answers my question and nothing more:
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using Microsoft.CSharp;
using System.CodeDom.Compiler;
using System.Reflection;
namespace MamaProgram
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
private void Form1_Load(object sender, EventArgs e)
{
string source =
#"
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.Net;
using MyMama = MamaProgram;
namespace Baby
{
public class Program
{
public WebBrowser wb = new WebBrowser();
public void navigateTo(string url)
{
wb.Navigated += wb_navigated;
wb.Navigate(url);
}
public void wb_navigated(object sender, WebBrowserNavigatedEventArgs e)
{
MyMama.Form1.getResult(wb.DocumentText);
}
}
}
";
Dictionary<string, string> providerOptions = new Dictionary<string, string>
{
{"CompilerVersion", "v3.5"}
};
CSharpCodeProvider provider = new CSharpCodeProvider(providerOptions);
CompilerParameters compilerParams = new CompilerParameters
{
GenerateInMemory = true,
GenerateExecutable = false,
TreatWarningsAsErrors = false
};
compilerParams.ReferencedAssemblies.Add(Assembly.GetExecutingAssembly().Location);
compilerParams.ReferencedAssemblies.Add("System.Data.dll");
compilerParams.ReferencedAssemblies.Add(typeof(System.Linq.Enumerable).Assembly.Location); // Trick to add assembly without knowing their name
compilerParams.ReferencedAssemblies.Add(typeof(System.ComponentModel.Component).Assembly.Location); // Trick to add assembly without knowing their name
compilerParams.ReferencedAssemblies.Add("System.Windows.Forms.dll");
CompilerResults results = provider.CompileAssemblyFromSource(compilerParams, source);
if (results.Errors.Count != 0)
throw new Exception("Compilation failed");
object o = results.CompiledAssembly.CreateInstance("Baby.Program");
MethodInfo mi2 = o.GetType().GetMethod("navigateTo");
mi2.Invoke(o, new object[] { "http://www.google.com" });
}
public static void getResult(string result)
{
MessageBox.Show(result);
}
}
}