CODEWITHSUNDEEP
c#uwp
Vague
Vague

Reputation: 2280

Convert StorageFile to string

We need to store an image file as a string in a UWP app. This was the plan:

FileOpenPicker picker = new FileOpenPicker();
picker.FileTypeFilter.Add(".png");
StorageFile file = await picker.PickSingleFileAsync();
byte[] fileBytes = File.ReadAllBytes(file.Path);
string fileString = Convert.ToBase64String(fileBytes);

but the line

byte[] fileBytes = File.ReadAllBytes(file.Path);

throws

System.UnauthorizedAccessException Access to the path 'C:\MyFolder\ImageFile.png' is denied.

For this exercise Everyone has Full Control permission on the file. I've also moved the file to various locations including a USB stick but always get the same exception. I assume this is a UWP thing rather than a permissions thing?

How do we save an image file as a string in a UWP app?

Upvotes: 1

Views: 1351

Answers (2)

TheTanic
TheTanic

Reputation: 1638

You get the exception, because in UWP you only can access to files over the path, is in the App-Package area.

To solve your problem you can use the IBuffer extension ToArray:

 IBuffer buffer = await FileIO.ReadBufferAsync(file);
 string fileString = Convert.ToBase64String(buffer.ToArray());

Upvotes: 2

Jeong Yo Han
Jeong Yo Han

Reputation: 600

you can't directly access to a file with string path. In UWP, you should always access file with Storage(File, Folder)check this
to get Bytes, you can use FileIO class or Open Stream with StorageFile.

Upvotes: 0

Related Questions