What's the difference between doing the following:
async Task<T> method(){
var r = await dynamodb.GetItemAsync(...)
return r.Item;
}
vs
async Task<T> method(){
var task = dynamodb.GetItemAsync(...)
return task.Result.Item;
}
In my case, for some reason, only the second works. The first one never seems to end.
await asynchronously unwraps the result of your task, whereas just using Result would block until the task had completed.
await case. You just mistakenly think it does because the method itself returns. But the task being awaited likely does not complete either way. If you want an answer to that (which is a different question than the one you asked), you need to post a new question, stating that clearly, and providing a good, minimal, complete code example that reliably reproduces the problem.
Result bare is a hidden deadlock..Result or all of its possible variants cause a threadpool thread to wait for a job on the thread pool to finish. This can exhaust all threads on the threadpool leaving none to perform the actual work.
.Result causes the current thread to block and wait for the result. await allows the current thread to go off and be useful doing other work while the result is being produced.task.Result is accessing the property's get accessor blocks the calling thread until the asynchronous operation is complete; it is equivalent to calling the Wait method. Once the result of an operation is available, it is stored and is returned immediately on subsequent calls to the Result property. Note that, if an exception occurred during the operation of the task, or if the task has been cancelled, the Result property does not return a value. Instead, attempting to access the property value throws an AggregateException exception. The only difference is that the await will not block. Instead, it will asynchronously wait for the Task to complete and then resume
Result bare is a hidden deadlock.