How do you run multiple async operations concurrently?

Intermediate

Answer

Start the tasks without awaiting each immediately, then await Task.WhenAll to run them in parallel and wait for all.

var t1 = h.GetStringAsync(a);
var t2 = h.GetStringAsync(b);
var r = await Task.WhenAll(t1, t2);

Real-world example Fetching price, stock and reviews at once to cut page latency.