WPF异步加载BitmapImage

在WPF中异步获取HTTP图片并赋值给Image控件,遇到诸多问题,如多线程队列,资源不释放等,最终琢磨出下面的方式:

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BackgroundWorker worker = new BackgroundWorker();
worker.DoWork += (s, e) =>
{
Uri uri = e.Argument as Uri;

using (WebClient webClient = new WebClient())
{
webClient.Proxy = null;
webClient.CachePolicy = new RequestCachePolicy(RequestCacheLevel.Default);
try
{
byte[] imageBytes = null;

imageBytes = webClient.DownloadData(uri);

if (imageBytes == null)
{
e.Result = null;
return;
}
MemoryStream imageStream = new MemoryStream(imageBytes);
BitmapImage image = new BitmapImage();

image.BeginInit();
image.StreamSource = imageStream;
image.CacheOption = BitmapCacheOption.OnLoad;
image.EndInit();

image.Freeze();
imageStream.Close();

e.Result = image;
}
catch (WebException ex)
{
e.Result = ex;
}
}
};

worker.RunWorkerCompleted += (s, e) =>
{
BitmapImage bitmapImage = e.Result as BitmapImage;
if (bitmapImage != null)
{
myImage.Source = bitmapImage;
}
worker.Dispose();
};

worker.RunWorkerAsync(imageUri);

WPF异步加载BitmapImage

https://wurang.net/wpf_get_bitmapimage/

作者

Wu Rang

发布于

2014-11-24

更新于

2021-04-02

许可协议


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