UWP保存图片时颜色反相【已解决】

从网上找的代码，把UWP的Xaml的UIElement截图保存到剪贴板中，但是发现颜色都反了。代码和截图如下。

具体原因是由于 BitmapPixelFormat.Rgba8引起的，换成 BitmapPixelFormat.Bgra8 之后就好了。

            //RenderTargetBitmap to render UIElement to image byte data array
            RenderTargetBitmap renderTargetBitmap = new RenderTargetBitmap();
            await renderTargetBitmap.RenderAsync(LeftPanel, wid, hei);
            var pixelBuffer = await renderTargetBitmap.GetPixelsAsync();
            var pixels = pixelBuffer.ToArray();
            //MemoryStream to save image data to
            var stream = new InMemoryRandomAccessStream();
            //BitmapEncoder to convert data and save to Stream
            var encoder = await BitmapEncoder.CreateAsync(BitmapEncoder.PngEncoderId, stream);
            encoder.SetPixelData(BitmapPixelFormat.Rgba8,//这里是重点
                        BitmapAlphaMode.Straight,
                        (uint)wid,
                        (uint)hei,
                        DisplayInformation.GetForCurrentView().RawDpiX,
                        DisplayInformation.GetForCurrentView().RawDpiY,
                        pixels);
            await encoder.FlushAsync();
            //Save Image data into ClipBoard
            DataPackage dataPackage = new DataPackage();
            dataPackage.SetBitmap(RandomAccessStreamReference.CreateFromStream(stream));
            //Copy image to Clipboard
            Clipboard.SetContent(dataPackage);

UWP Application的颜色

 保存到剪贴板的图片