在等待 GetAsync 的结果时定期做一些事情

Question

我想开始一个 GetAsync 或 PostAsync，然后循环执行一些操作并检查结果。

req1 = client.GetAsync(url_1); // a time consuming request

do
{
    //do something here
    var req2= await client.GetAsync(url_2);
    var result2 = await req2.Content.ReadAsStringAsync();
    
} while (!IsResultReady(req1)); // check if url_1 job is done and stop the loop

var result1 = await req1.Content.ReadAsStringAsync();

Answer 1

这个例子应该能满足您的需求

async Task Main()
{
    var mainTask = MyLongRunningTask();
    // mainTask is already started without await
    do
    {
        await DoSomethingElse();
    } while (!mainTask.IsCompleted);
}

public async Task MyLongRunningTask()
{
    Console.WriteLine("Long Running Task Started");
    
    await Task.Delay(3000); // simulating client.GetAsync(url_1)
    
    Console.WriteLine("Long Running Task Finished");
}

async Task DoSomethingElse()
{
    Console.WriteLine("doing some other tasks");
    await Task.Delay(1000);
}

输出：

Long Running Task Started
doing some other tasks
doing some other tasks
doing some other tasks
Long Running Task Finished

在等待 GetAsync 的结果时定期做一些事情

Do something periodically while waiting for result of an GetAsync

c#

wpf

asynchronous

async-await

getasync