Why async programming is needed in C Sharp (C#) - Test Your Understanding

Practice - 5 Tasks

1fill in blank

easy

Complete the code to start an asynchronous task.

C Sharp (C#)

Task.Run(() => [1]);

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ADoWork()

Bawait DoWork()

CDoWork

Dasync DoWork()

Attempts:

3 left

💡 Hint

Common Mistakes

Using await inside Task.Run without async lambda.

Passing method name without parentheses.

Task.Run expects a delegate or method call. Using DoWork() calls the method synchronously inside the task.

2fill in blank

medium

Complete the code to await an asynchronous method.

C Sharp (C#)

await [1]();

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ADoWork

BRunWork

CDoWorkAsync

DStartWork

Attempts:

3 left

💡 Hint

Common Mistakes

Awaiting a synchronous method.

Calling async method without await.

By convention, asynchronous methods end with Async. You await the async method to pause until it completes.

3fill in blank

hard

Fix the error in the async method declaration.

C Sharp (C#)

public async [1] DoWorkAsync() { await Task.Delay(1000); }

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ATask

Bint

Cvoid

Dasync

Attempts:

3 left

💡 Hint

Common Mistakes

Using void as return type for async method.

Returning int from async method.

Async methods that do not return a value must return Task, not void or other types.

4fill in blank

hard

Fill both blanks to create a dictionary of tasks and await their completion.

C Sharp (C#)

var tasks = new Dictionary<string, Task> { {"task1", [1] }, {"task2", [2] } };
await Task.WhenAll(tasks.Values);

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ADoWorkAsync()

BDoWork()

CRunAsync()

DRun()

Attempts:

3 left

💡 Hint

Common Mistakes

Using synchronous methods in the dictionary.

Not awaiting Task.WhenAll.

We store asynchronous method calls returning Task in the dictionary and then await all tasks together.

5fill in blank

hard

Fill all three blanks to create an async method that returns a string after delay.

C Sharp (C#)

public async Task<string> [1]() {
    await Task.Delay([2]);
    return [3];
}

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AGetDataAsync

B1000

C"Done"

DFetchData

Attempts:

3 left

💡 Hint

Common Mistakes

Using synchronous method name.

Returning a non-string value.

Incorrect delay time format.

The method name ends with Async, delay is 1000 milliseconds, and it returns the string "Done".