我有以下代码在一个Windows 8 C#应用程序中,从服务器获取并存储图像:
private async Task httpFetcher()
{
HttpClient httpClient = new HttpClient();
HttpRequestMessage request = new HttpRequestMessage(
HttpMethod.Get, "http://www.example.com/fakeImageRotator.php"); // FOR EXAMPLE
HttpResponseMessage response = await httpClient.SendAsync(request,
HttpCompletionOption.ResponseHeadersRead);
Uri imageUri;
BitmapImage image = null;
try
{
var imageFile = await ApplicationData.Current.LocalFolder.CreateFileAsync(
"test.png", CreationCollisionOption.ReplaceExisting);
var fs = await imageFile.OpenAsync(FileAccessMode.ReadWrite);
DataWriter writer = new DataWriter(fs.GetOutputStreamAt(0));
writer.WriteBytes(await response.Content.ReadAsByteArrayAsync());
await writer.StoreAsync();
writer.DetachStream();
await fs.FlushAsync();
writer.Dispose();
if (Uri.TryCreate(imageFile.Path, UriKind.RelativeOrAbsolute, out imageUri))
{
image = new BitmapImage(imageUri);
}
}
catch (Exception e)
{
return;
}
image1.Source = image;
}
看起来我在这一行随机出现了错误:
var imageFile = await ApplicationData.Current.LocalFolder.CreateFileAsync(
"test.png", CreationCollisionOption.ReplaceExisting);
这种情况并不总是发生,所以我不确定如何确定问题所在。以下是所有错误细节:
捕获到UnauthorizedAccessException
访问被拒绝。(HRESULT 异常:0x80070005 (E_ACCESSDENIED)) 位于 System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task) 位于 System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task) 位于 System.Runtime.CompilerServices.TaskAwaiter`1.GetResult() 位于 TestApp.MainPage.d__4.MoveNext() in d:\TestApp\TestApp\MainPage.xaml.cs:line 86
var stream = await imageFile.OpenAsync(Windows.Storage.FileAccessMode.Read);
处遇到了一个UnauthorizedAccessException(访问被拒绝。(HRESULT:0x80070005(E_ACCESSDENIED)的异常))。这次可能是权限问题?有什么想法? :/ - ReignOfComputer