How to convert "Webclient" to "async/await"?

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1

I have code that checks if you have the internet or not.

public static bool InternetIsConnected()
{
    try
    {
        using (var client = new WebClient())
        {
            using (client.OpenRead("http://clients3.google.com/generate_204"))
            {
                return true;
            }
        }
    }
    catch
    {
        return false;
    }
}

How to convert code to async/await ?

Update:

Attempt 1: (Comment from @Virgilio Novic)

public async bool InternetIsConnected()
{
    try
    {
        using (var client = new WebClient())
        {
            Uri uri = new Uri("http://clients3.google.com/generate_204");
            using (await client.OpenReadAsync(uri))
            {
                return true;
            }
        }
    }
    catch
    {
        return false;
    }
}

Above code gives error: "Unable to wait void".

Using the class "Ping": (Functional)

private async Task<bool> InternetIsConnected()
{
    Ping ping = new Ping();
    try
    {
        await ping.SendPingAsync("google.com", 3000, new byte[32], new PingOptions(64, true));
        return true;

    }
    catch (Exception)
    {
        return false;
    }
}
c#
  • 1

    related: https://msdn.microsoft.com/pt-br/library/ms144211(v=vs.110). aspx

  • @Virgilionovic I tried to do, it gives error, says it is not possible to wait void.

  • 1

    public async Task<bool> InternetIsConnected() that’s the way it is

  • 1

    Other Reading: https://stackoverflow.com/questions/25051674/how-to-wait-for-webclient-openreadasync-to-complete

  • @Virgilionovic, updated post. See what the class thinks Ping. Or better to use WebClient ?

  • what I usually do, is run in or another Thread, and it will not be necessary to use the await.

  • @Text can give me an example of code ?

  • 1

    @Matheusmiranda void nome_da_void(){webclient.OpenRead(xxx);/*isso não 'trava seu código'*/} void NOME_OUTRA_VOID(){Thread th = new Thread(nome_da_void);th.Start();}

  • @More how I will get the return of true or false ?

  • 1

    @Matheusmiranda you can create a bool, and put a Try and catch (as you did in the code of your question); if the catch is called, that bool will be false.

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1 answer

1

You must use the method OpenReadTaskAsync, this yes supports async/await, the OpenReadAsync existed before async/await and triggers an event when the operation is complete, I believe that is why they had to give this other name to the method to be able to support async/await

Another detail is that the return of an async method should always be one Task

public async Task<bool> InternetIsConnected()
{
    try
    {
        using (var client = new WebClient())
        {
            Uri uri = new Uri("http://clients3.google.com/generate_204");
            using (await client.OpenReadTaskAsync(uri))
            {
                return true;
            }
        }
    }
    catch
    {
        return false;
    }
}

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