Why can't I post from my Xamarin Frorms app to my .net core web api

Question

I have a post method that sends json to my api.

My endpoint works in postman so my problem is in my xamarin post request:

    async void RegisterUser(o         


        

Answer 1

So after 2 days of googling i found a solution:

https://marketplace.visualstudio.com/items?itemName=vs-publisher-1448185.ConveyorbyKeyoti#overview

now I can post to my api from my xamarin forms project!!!

thanks for everyone's input

Answer 2

Please test the Web Api with some REST testing tool like POSTMAN, to verify that it works with your JSON data firstly.

If your webapi have no problems, please take a look the following code, I can post data to asp.net core webapi successfully, and return value.

 private async void btnpost_Clicked(object sender, EventArgs e)
    {
        ContactModel cm = new ContactModel() {ID=1,Name="cherry",Age=12 };

        var httpClient = new HttpClient();
        var content = JsonConvert.SerializeObject(cm);
        HttpContent httpContent = new StringContent(content, Encoding.UTF8);
        httpContent.Headers.ContentType = new MediaTypeHeaderValue("application/json");
        var uri = new Uri("http://xxx.xx.xx.xx:8088/api/Contact");
        HttpResponseMessage response = await httpClient.PostAsync(uri, httpContent);
        if (response.IsSuccessStatusCode)
        {
            var data = await response.Content.ReadAsStringAsync();

            string ss = data;
        }

    }

Please note: Adding android:usesCleartextTraffic="true" in Mainfeast.xml,because starting with Android 9 (API level 28), cleartext support is disabled by default. if not, you may have Cleartext HTTP traffic not permitted error.