Uwp 任务。跳过延迟
我的目标是在uwp中反复播放音频文件。中间是一个等待时间,它会改变 问题是waitingtime总是被跳过 这就是我所尝试的:Uwp 任务。跳过延迟,uwp,task,Uwp,Task,我的目标是在uwp中反复播放音频文件。中间是一个等待时间,它会改变 问题是waitingtime总是被跳过 这就是我所尝试的: private async Task Characteristic_ValueChanged(GattCharacteristic sender, GattValueChangedEventArgs args) { while (true) { var t = Task.Run(delegate {
private async Task Characteristic_ValueChanged(GattCharacteristic sender, GattValueChangedEventArgs args)
{
while (true)
{
var t = Task.Run(delegate
{
abspielenAsync();
return 42;
});
t.Wait();
}
}
private async void abspielenAsync()
{
if (neu)
{
await Windows.ApplicationModel.Core.CoreApplication.MainView.CoreWindow.Dispatcher.RunAsync(CoreDispatcherPriority.Normal,
() =>
{
mysong = new MediaElement();
});
Windows.Storage.StorageFolder folder = await Windows.ApplicationModel.Package.Current.InstalledLocation.GetFolderAsync("Assets");
Windows.Storage.StorageFile file = await folder.GetFileAsync("he.wav");
var stream = await file.OpenAsync(Windows.Storage.FileAccessMode.Read);
await Windows.ApplicationModel.Core.CoreApplication.MainView.CoreWindow.Dispatcher.RunAsync(CoreDispatcherPriority.Normal,
() =>
{
mysong.SetSource(stream, file.ContentType);
});
neu = false;
}
await Windows.ApplicationModel.Core.CoreApplication.MainView.CoreWindow.Dispatcher.RunAsync(CoreDispatcherPriority.Normal,
() =>
{
mysong.Play();
while(mysong.CurrentState == Windows.UI.Xaml.Media.MediaElementState.Playing)
{
}
});
await Task.Delay((int)(waitingtime * 1000));
Debug.WriteLine((waitingtime * 1000).ToString());
}
这将始终立即返回:
var t = Task.Run(delegate
{
abspielenAsync();
return 42;
});
t.Wait();
您的abspielenancy
方法未返回任务,因此无法等待。因此,您只是在后台运行它,而不是等待它(通常称为“开火并忘记”)
如果在返回42
之前要等待abspielenancy()
完成,请使abspielenancy
方法返回Task
,并将其调用位置更改为await abspielenancy()代码>@Gabriel告诉我们为什么代码不运行
我们需要更改abspielenancy
中的代码以使任务运行
private async void abspielenAsync()
我们应该将void
更改为Task
,并在任务中等待它
private async Task abspielenAsync()
然后我们应该改变特征值中的代码
while (true)
{
var t = Task.Run(async () =>
{
await abspielenAsync();
return 42;
});
t.Wait();
}
方法名称应命名为。看