从本地存储加载图片> OutofmemoryException-C＃-Xamarin.Forms

Question

When i want to load pictures from internal storage, sometimes its to laggy but sometimes i get OutOfMemmoryException.

var picList = System.Instance.GetFiles("/storage/emulated/0/DCIM/Camera", true); //Its a string list, include the files name


                var inc = 0;

                foreach (var item in picList)
                {

                    var byteArray = FileSystem.Instance.ReadFile("/storage/emulated/0/DCIM/Camera", item.Split('/').Last(), true);

                    var toPicture = ImageSource.FromStream(() => new MemoryStream(byteArray));

                    var image = new Image
                    {
                        ClassId = inc.ToString(),
                        Source = toPicture,
                        WidthRequest = 200,
                        HeightRequest = 200,
                    };
    `        }
    }

I think i need to dispose it but i dont know how.

Answer 1

Most likely you never invoke image.Dispose() method on image instance so memory allocated to image is never released. Also you should consider not loading all files but load them on demand.

Answer 2

I think you should declare your variables outside the loop and reuse them, instead of declaring new ones at each iteration :

byte[] byteArray = null;
MemoryStream toPicture = null;
Image image = null;  

foreach (var item in picList)
{
    byteArray = FileSystem.Instance.ReadFile("/storage/emulated/0/DCIM/Camera", item.Split('/').Last(), true);

    toPicture = ImageSource.FromStream(() => new MemoryStream(byteArray));

    image = new Image
    {
        ClassId = inc.ToString(),
        Source = toPicture,
        WidthRequest = 200,
        HeightRequest = 200,
    };
}