In WinRT, how do I load an image and then wait only as long as is needed for it to load before writing to it?

Question

I\'m using WriteableBitmapEx in a WinRT project. I load an image into a WriteableBitmap from the users Picture library. However, I cannot then immediately write to that im

Answer 1

The OpenAsync returning just means the stream is available, not that the data is actually read from it. It seems like you would therefore want to both open + read first and then you would be fine.

Since Filip pointed out that ReadAsync would require you to create and pass in a buffer first, I've updated the below snippet to use DataReader to actually load the stream into the byte array after doing OpenReadAsync to get the IRandomAccessStream.

var randomAccessStream = await file.OpenReadAsync();

var dataReader = new DataReader(randomAccessStream);
await dataReader.LoadAsync(randomAccessStream.Size);

byte[] imageBytes;
dataReader.ReadBytes(out imageBytes);

wbm.SetSource(new MemoryStream(imageBytes));