2

I want to start a bunch of tasks and wait for all of them to finish.

This question is more or less identical to this question: Executing tasks in parallel

But, the answer is not same for Silverlight because there is no equivalent method to Task.WhenAll().

This should work, but I get an error

Start may not be called on a promise-style task.

        foreach (var displayThumbnailTask in displayThumbnailTasks)
        {
            displayThumbnailTask.Start();
        }

        foreach (var task in displayThumbnailTasks)
        {
            await task;
        }
Christian Findlay
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1 Answers1

3

"Start may not be called on a promise-style task." is a somewhat misleading message for the simple thing: the task has already been started.

Thus, you may just omit the first loop.

Silverlight does not have Task.WhenAll, but if you are using Microsoft.Bcl.Async, it contains TaskEx.WhenAll which is the same.

await TaskEx.WhenAll(displayThumbnailTasks);

Execute parallel tasks with async/await

dvorn
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