Send HTTP POST message in ASP.NET Core using HttpClient PostAsJsonAsync : <p>I want to send dynamic object like</p>

<pre><code>new { x = 1, y = 2 };
</code></pre>

<p>as body of HTTP POST message. So I try to write</p>

<pre><code>var client = new HttpClient();
</code></pre>

<p>but I can't find method </p>

<pre><code>client.PostAsJsonAsync()
</code></pre>

<p>So I tried to add Microsoft.AspNetCore.Http.Extensions package to project.json and add </p>

<pre><code>using Microsoft.AspNetCore.Http.Extensions; 
</code></pre>

<p>to uses clause. However It didn't help me.</p>

<p>So what is the easiest way to send POST request with JSON body in ASP.NET Core?</p>
