Question

In windows phone 7 I’m doing a simple async lookup to find an image by uri and set the returned binary as the source for an image control.

public object SetImageFromUri(string uri)
{
    var wc = new WebClient();
    wc.OpenReadCompleted += new OpenReadCompletedEventHandler(wc_OpenReadCompleted);
    wc.OpenReadAsync(new Uri(uri), wc);

    return null;
}

void wc_OpenReadCompleted(object sender, OpenReadCompletedEventArgs e)
{
    if (e.Error == null && !e.Cancelled)
    {
            var image = new BitmapImage();
            image.SetSource(e.Result);

            //e.Result has a property in the memory stream labeled finalUri
            //someImageControl.Source = image;

    }
}

My question is- how can I pull out the final uri property from the e.Result so I can see what image control it’s associated with

Thank you in advance

Answer 1

Instead of passing the WebClient through as the second parameter, pass the Uri (or some other piece of usefule state information)

wc.OpenReadAsync(new Uri(uri), uri);

You can then access this in your callback

var uri = (string)e.UserState;