title: 'IFormFile' could not be found (are you using a directive or assembly reference?)
body: <p>I've created a .net standard project in vs2017.
  Now I'm going to create a model in the form below</p>
  
  <pre><code>public IList &lt;IFormFile&gt; files {get; set; }
  </code></pre>
  
  <p>But despite adding a guide</p>
  
  <pre><code>using Microsoft.AspNetCore.Http;
  </code></pre>
  
  <p>I encounter the following error
  The type or namespace name 'IFormFile' could not be found (are you using a directive or assembly reference?)
  What is the objection? Please guide me thank you</p>