Can't write file in USB flash drive with Xamarin Android/Uwp

Question

I have some troubles. It's about this subject => System.UnauthorizedAccessException : Access to the path “/storage/[Name]/[nameFolder]/[fileName].txt is denied. At System.IO.FileStream etc….

I know this subject is already here in SOF, but I can't find a solution for Xamarin.Android. It's the same for Xamarin.Uwp, no access right.

I can't write a file in the root path (from the USB Flash Drive path) =

/storage/[NameOfTheFlashDrive]

It's the same if I use the Android path =

content://com.android.externalstorage.documents/documents/[NameOfTheFlashDrive]

Same message > System.UnauthorizedAccessException Access to the path

I don't know how to proceed.

I have used =

File.WriteAllText(filePath, Data);

And I have the permissions to write file in external storage.

The only solution is to use Plugin.Essential or PickerFile and save manually in the correct path.

If someone have a idea to proceed with the right way.

Thank you. Zebiphire.

Answer 1

I have some troubles. It's about this subject => System.UnauthorizedAccessException : Access to the path “/storage/[Name]/[nameFolder]/[fileName].txt is denied. At System.IO.FileStream etc….

According to your error message, I guess that you ma need to enbale permission in runtime.

You should enable READ_EXTERNAL_STORAGE and WRITE_EXTERNAL_STORAGE permissions in Android and UWP.