在FlUrl中我尝试使用EnableCookies（）并抛出一个空引用异常

Question

when I try to execute:

            using (var fc = new FlurlClient().EnableCookies())
            {
                var resp = "http://somesite.com".GetAsync();
                // var getResp = await "http://api.foo.com".GetAsync();

                var resultado = await resp;

                var x = resultado;
            }

I get a null reference exception on EnableCookies()

stack:

   en Flurl.Url.op_Implicit(Url url) en C:\Aldenteware\Flurl\code\Flurl\Url.cs:línea 315
   en Flurl.Http.CookieExtensions.GetCookieContainer(FlurlClient client) en C:\Aldenteware\Flurl\code\Flurl.Http.Shared\CookieExtensions.cs:línea 145
   en Flurl.Http.CookieExtensions.EnableCookies(FlurlClient client) en C:\Aldenteware\Flurl\code\Flurl.Http.Shared\CookieExtensions.cs:línea 23
   en AfipProcesa.Form1.<flurlAsync>d__0.MoveNext() en c:\Users\fabian.LH\Documents\Visual Studio 2013\Projects\AfipProcesa\AfipProcesa\Form1.cs:línea 86
--- Fin del seguimiento de la pila de la ubicación anterior donde se produjo la excepción ---
   en System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
   en System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   en AfipProcesa.Form1.<button1_Click>d__7.MoveNext() en c:\Users\fabian.LH\Documents\Visual Studio 2013\Projects\AfipProcesa\AfipProcesa\Form1.cs:línea 119
--- Fin del seguimiento de la pila de la ubicación anterior donde se produjo la excepción ---
   en System.Runtime.CompilerServices.AsyncMethodBuilderCore.<ThrowAsync>b__4(Object state)

I have to do something more or in another way?

I put it on a flurl error handler but it not catch it (as it is a null ex)

I starting to use await/async and flurl at same time... sorry if I'm making a basic mistake.

I using as a example the code on http://tmenier.github.io/Flurl/client-lifetime/

using (var fc = new FlurlClient().EnableCookies())
{
    await url
        .AppendPathSegment("login")
        .WithClient(fc)
        .PostUrlEncodedAsync(new { user = "user", pass = "pass" });

    var page = await url
        .AppendPathSegment("home")
        .WithClient(fc)
        .GetStringAsync();

    // Need to inspect the cookies? FlurlClient exposes them as a dictionary.
    var sessionId = fc.Cookies["session_id"].Value;
}

Answer 1

It looks like you've spotted a bug related to recent changes to address this issue . The work-around is to seed FlurlClient with the base URL:

using (var fc = new FlurlClient(url).EnableCookies())

I'll log this issue and address it soon, it clearly doesn't work as documented.