Android Emulator with Localhost ASP.Net Core API Calls

Question

I've been trying to perform a GET request from Visual Studio's Android Emulator to an ASP.Net Core API running on localhost. I first read that I have to use IP 10.0.2.2 when performing the request from Android, so I have the following HTTP client code in my Android (Xamarin) App

protected override void OnCreate(Bundle bundle)
        {
            base.OnCreate(bundle);
            SetContentView (Resource.Layout.Main);

            var logInbutton = FindViewById<Button>(Resource.Id.logInButton);

            logInbutton.Click += OnLogInButtonClicked;
        }

        private async void OnLogInButtonClicked(object sender, EventArgs e)
        {
            using (var client = new HttpClient())
            {
                client.DefaultRequestHeaders.Accept.Clear();
                client.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));


                var uri = new Uri("http://10.0.2.2:5555/api/Orders?api-version=0.9");
                var response = await client.GetAsync(uri);
            }
        }

However, each time I attempt to run this I'm greeted with a 400 Bad Request error. I know the request is okay since I can run the same Http client code from a console app without any errors. I then read that IIS express does not accept external requests and since the Android emulator is running in a VM this could be the reason.

So I then followed the advice on this SO post but was greeted with an Invalid URI: The hostname could not be parsed error. I'm not sure how to proceed from here. Is there a solution to the Invalid URI: The hostname could not be parsed error, or should I attempt to circumvent IIS Express and run solely with kestrel for development? Would even running solely in kestrel fix this problem?

The often quoted solution is to change config files, but you can avoid that with our free VS Extension called Conveyor, https://marketplace.visualstudio.com/items?itemName=vs-publisher-1448185.ConveyorbyKeyoti — Jim W, Apr 12 '18 at 19:46

score 0 · Answer 1 · answered Jul 19 '17 at 01:04

I had a similar issue.

First, let's locate the correct applicationhost.config file. You should check this location:

[solution folder]/.vs/config/applicationhost.config

Then people advice to set up binding like this:

<binding protocol="http" bindingInformation="*:5555:*" />

It did NOT work for me. I received "Invalid URI: The hostname could not be parsed".

What did work for me is the syntax like this:

<binding protocol="http" bindingInformation=":5555:" />

Please note, port 5555 is given as example. You should use the port your server is listening to.

score 0 · Answer 2 · answered Nov 04 '21 at 11:56

0

I ran into the same issue when attempting to connect while running through kestrel. For me it worked using this configuration for the launchsettings:

answered Nov 04 '21 at 11:56

Dbl

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Android Emulator with Localhost ASP.Net Core API Calls

2 Answers2