Concurrent Tasks with WhenAll
Run independent asynchronous operations concurrently.
Introduction
Task.WhenAll completes when every supplied task has finished.
Starting both tasks before awaiting them allows their delays to overlap.
Runnable C# example
Program.cs
using System;
using System.Threading.Tasks;
class Program
{
static async Task<int> Fetch(int value) { await Task.Delay(20); return value; }
static async Task Main()
{
int[] results = await Task.WhenAll(Fetch(20), Fetch(22));
Console.WriteLine(results[0] + results[1]);
}
}
42Practice with the debugger
Set a breakpoint on an important assignment or condition, click Debug, and inspect the local values before stepping to the next line.
Practice with a challenge
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