loading the source of a BitmapImage in WPF?

问题

In a silverlight app, I have a BitmapImage defined as System.Windows.Media.Imaging.BitmapImage and it as a method called "SetSource" where I can set the source like this:

BitmapImage bitmap = new BitmapImage();
System.IO.Stream stream = _scene.GetStream();
if (stream == null) return;
bitmap.SetSource(stream);

In a WPF application I have also have a Bitmap image defined as System.Windows.Media.Imaging.BitmapImage but there is no SetSource method. How do I set the source in a WPF app like I do in a Silverlight app?

Also, it is a stream, not a string. It is not a URI. so "UriSource" method does not work. I tried this:

        System.IO.Stream stream = _scene.GetStream();
        if (stream == null) return;
        BitmapImage bitmap = new BitmapImage();

        bitmap.UriSource = new Uri(stream.ToString());

And at runtime, it threw an error tha URI cannot be determined. Is the URI an identifier for the intranet? Are you sure that this is not a silverlight thing? I am doing a WPF application

回答1:

You'll have to set the BitmapImage.StreamSource property:

BitmapImage bitmap = new BitmapImage();
bitmap.BeginInit();
bitmap.StreamSource = _scene.GetStream();
bitmap.EndInit();

If you want to close the stream right after creating the bitmap, you would also have to set the BitmapCacheOption.OnLoad option:

using (Stream stream = _scene.GetStream())
{
    bitmap.BeginInit();
    bitmap.CacheOption = BitmapCacheOption.OnLoad;
    bitmap.StreamSource = stream;
    bitmap.EndInit();
}

回答2:

You can use the constructor to specify the UriSource

BitmapImage bmp = new BitmapImage(uriSource: new Uri());

Or you can use BitmapImage.StreamSource property to set the StreamSource

来源：https://stackoverflow.com/questions/11771223/loading-the-source-of-a-bitmapimage-in-wpf

标签

wpf

bitmapimage