I'm sure this has been asked before but I can't seem to phrase the question right to get any answers that solve my question.
I've got a base class that implements an interface with a Save method that returns a Task:
public interface ICanSave
{
Task Save();
}
public class Base : ICanSave
{
public Task Save()
{
return Task.CompletedTask;
}
}
Of course the Save method will actually do something, like saving to a database, which is why it's a Task, so it can be awaited. If I have a Foo class that inherits from the base class:
public class Foo : Base { }
Currently, you'd have to do the instantiation and save in two distinct steps:
var foo = new Foo();
await foo.Save();
However I'd like to be able to do the instantiation and the save as an expression and return a Task also. I've come up with this helper:
public static class Helper<T> where T : ICanSave
{
public static Task<T> Save(T obj)
{
var source = new TaskCompletionSource<T>();
ThreadPool.QueueUserWorkItem(_ =>
{
obj.Save();
source.SetResult(obj);
});
return source.Task;
}
}
Which could then be used to do:
var foo = await Helper<Foo>.Save(new Foo());
Which is more like the result I'm trying to achieve, but it seems pretty cumbersome, plus the helper seems to be pushing the Save to a Task twice (once for the original Task and a second time in the helper).
Is there a more simple way to do this conversion from a Task to a Task of T?
I don't see a point of such helper method, but if you really want you can like this:
public static class Helper<T> where T : ICanSave {
public static async Task<T> Save(T obj) {
await obj.Save();
return obj;
}
}
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