无法使用带有C＃Xamarin和Android的RestClient将数据发布到服务器

Question

I have tried posting to the server using the following code:

C#:

myButton.Click += delegate
{
    var url = "https://www.myurl.com/test.php";
    var client = new RestClient(url);
    var request = new RestRequest(Method.POST);
    request.AddParameter("A", "foo");
    request.AddParameter("B", "bar");
    var response = client.Execute(request);
    textView.Text = response.Content;
}

PHP:

<?php
    die('aaa'.$_POST['A'].$_POST['B']);
?>

The textView is being set to 'aaa', so it's receiving data from the server. The problem is the $_POST data is not being sent with request.AddParameter. I have also tried with var client = new RestClient("Resource", url);. That doesn't work either. Maybe "Resource" is incorrect.