public static async Task Run()
{
// Start concurrent work on background threads (thread pool.) using `Task.Run()`
Task printTask = PrimeNumbers.PrintPrimeNumbersConcurrent(MaxPrimeToPrint, ThreadsToUse);
Console.WriteLine($"Started to print all the prime numbers up to {MaxPrimeToPrint} " +
$"*concurrently* (using up to {ThreadsToUse} different threads) ...");
// Start asynchronous I/O task on the main thread by awaiting an `async` method.
Console.WriteLine("=== HttpClient().GetStringAsync() started! ===");
Task <string> webTask = new HttpClient().GetStringAsync(ExampleUrl);
Console.WriteLine($"Started to download web content from {ExampleUrl} *asynchronously* (on the main thread) ...");
Console.WriteLine($"While waiting for the website data, we can calculate what would be the " +
$"next prime number after {ExamplePrime} fully *synchronously* (blocking the main thread) ...");
// Start an async Task and run it completely synchronously blocking the main thread - Avoid doing this!
Task <int> primeTask = PrimeNumbers.PrintPrimeNumbersAndGetNextAsync(ExamplePrime, false);
int foundPrime = primeTask.Result;
//int foundPrime = primeTask.GetAwaiter().GetResult(); // This is incorrect use for us, as the GetAwaiter
// is meant to be used only by the compiler and not by the programmer.
// However it will achieve the same thing - get a result of the asynchronous method, synchronously,
// and they both block the main thread. Avoid using `.Result` as well, and correctly `await` everything :]
Console.WriteLine($"Found the prime number: {foundPrime}");
// Wait for the I/O task to finish, and get it's result.
string webContent = await webTask;
Console.WriteLine("=== HttpClient().GetStringAsync() done! ===");
Console.WriteLine($"Downloaded web content (1st line): {webContent.Split('\n')[0]}"); //writing only the first line...
// Wait for the concurrent CPU task to finish (it does not have a result.)
await printTask;
Console.WriteLine($"All done!");
}
public static async Task RunTest()
{
Console.WriteLine($"Looking for {PrimeToFind} prime numbers *synchronously* (1 main thread) ...");
Stopwatch watch = Stopwatch.StartNew();
// Synchronous code.
int prime = PrimeNumbers.FindNthPrime(PrimeToFind);
watch.Stop();
Console.WriteLine($"Synchronously found the {PrimeToFind}th prime number {prime} in {watch.ElapsedMilliseconds}ms");
Console.WriteLine($"Looking for {PrimeToFind} prime numbers *concurrently* ({ThreadsToUse} threads) ...");
watch.Restart();
// Immediately awaited asynchronous code executing multiple threads concurrently.
await PrimeNumbers.PrintPrimeNumbersConcurrent(prime, ThreadsToUse);
watch.Stop();
Console.WriteLine($"Concurrently found all the prime numbers up to {prime} in {watch.ElapsedMilliseconds}ms");
}
