How do I get a return value from Task.WaitAll() in a console app?

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You don’t get a return value from Task.WaitAll. You only use it to wait for completion of multiple tasks and then get the return value from the tasks themselves.

var task1 = GetAsync(1);
var task2 = GetAsync(2);
Task.WaitAll(task1, task2);
var result1 = task1.Result;
var result2 = task2.Result;

If you only have a single Task, just use the Result property. It will return your value and block the calling thread if the task hasn’t finished yet:

var task = GetAsync(3);
var result = task.Result;

It’s generally not a good idea to synchronously wait (block) on an asynchronous task (“sync over async”), but I guess that’s fine for a POC.

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