每当我创建 WriteableBitmap
的任何实例时,我都会发生内存泄漏。我在 stackoverflow 和其他论坛上尝试了多种建议,但没有任何效果。我的测试应用程序的基本流程是这样的:
- 使用
PhotoChooserTask
选择图像 - 使用
PhotoResult
对象中的Stream
创建一个WriteableBitmap
。
就是这样。清零变量并调用 GC.Collect()
只能解决部分问题。它会阻止应用程序分配内存,直到应用程序崩溃,但即使对象超出范围,在我选择新图像之前,总会为它们分配内存。我可以使用带有 XAML 应用程序的默认 Windows Phone Direct3D 重现它。对默认项目的唯一修改如下:
MainPage.xaml.cs
public MainPage() {
InitializeComponent();
_photoChooserTask = new PhotoChooserTask();
_photoChooserTask.Completed += new EventHandler<PhotoResult>(photoChooserTaskComplete);
}
private void ApplicationBarIconButton_Click(object sender, EventArgs e) {
_photoChooserTask.Show();
}
private void photoChooserTaskComplete(object sender, PhotoResult e) {
if (e.TaskResult == TaskResult.OK) {
BitmapImage image = new BitmapImage();
image.SetSource(e.ChosenPhoto);
WriteableBitmap wbm = new WriteableBitmap(image);
image.UriSource = null;
image = null;
wbm = null;
GC.Collect();
}
}
主页.xaml
<phone:PhoneApplicationPage.ApplicationBar>
<shell:ApplicationBar IsVisible="True" IsMenuEnabled="True" Mode="Default" Opacity="0.5" >
<shell:ApplicationBar.Buttons>
<shell:ApplicationBarIconButton IconUri="/junkUrl.png" Text="albums" Click="ApplicationBarIconButton_Click" />
</shell:ApplicationBar.Buttons>
</shell:ApplicationBar>
</phone:PhoneApplicationPage.ApplicationBar>
最佳答案
为此,您必须将此文件流存储在 IsolatedStorege 中。所以使用 IsolatedStorageFileStream 创建一个文件流,然后保存它,就像这样......
private void photoChooserTaskComplete(object sender, PhotoResult e) {
if (e.TaskResult == TaskResult.OK) {
SaveToIsolatedStorage(e.ChosenPhoto,"Your File Name");
}
public void SaveToIsolatedStorage(Stream imageStream, string fileName)
{
try
{
string imagename = fileName + ".jpg";
using (IsolatedStorageFile myIsolatedStorage = IsolatedStorageFile.GetUserStoreForApplication())
{
if (myIsolatedStorage.FileExists(imagename))
{
myIsolatedStorage.DeleteFile(imagename);
}
IsolatedStorageFileStream fileStream = myIsolatedStorage.CreateFile(imagename);
WriteableBitmap wb = new WriteableBitmap(100, 100);
wb.SetSource(imageStream);
wb.SaveJpeg(fileStream, 100, 100, 0, 70);
fileStream.Close();
}
}
catch (Exception)
{
RadMessageBox.Show(String.Empty, MessageBoxButtons.OK, "Error occured while saving Images");
}
}
为了阅读,您可以从 IsolatedStorage 获取该文件
public WriteableBitmap ReadFromIsolatedStorage(string fileName)
{
WriteableBitmap bitmap = new WriteableBitmap(100, 100);
try
{
using (IsolatedStorageFile myIsolatedStorage = IsolatedStorageFile.GetUserStoreForApplication())
{
if (myIsolatedStorage.FileExists(fileName))
{
using (IsolatedStorageFileStream fileStream = myIsolatedStorage.OpenFile(fileName, FileMode.Open, FileAccess.Read))
{
// Decode the JPEG stream.
bitmap = PictureDecoder.DecodeJpeg(fileStream, 100, 100);
}
}
}
}
catch (Exception)
{
RadMessageBox.Show(String.Empty, MessageBoxButtons.OK, "Error Occcured while reading image");
}
return bitmap;
}
这将解决您的内存泄漏问题,试试这个...
关于c# - Windows Phone 8 中的 WriteableBitmap 内存泄漏,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/18348023/