title: Post file using httpclient fluent API
body: <p>I always using httpclient fluent api to post messages because of the code is very clean.
  example :</p>
  
  <pre><code>String html = Request.Post("URL")
               .connectTimeout(2000).socketTimeout(2000)
               .bodyForm(Form.form().add("type", "image").build(), Charset.forName("UTF8"))
               .execute().returnContent().asString();
  </code></pre>
  
  <p>After reading the httpclient document, I have found this:</p>
  
  <pre><code>MultipartEntityBuilder builder = MultipartEntityBuilder.create();
  builder.setMode(HttpMultipartMode.BROWSER_COMPATIBLE);
  builder.setCharset(Charset.forName(CHARSET));
  builder.addBinaryBody("media", bytes, ContentType.MULTIPART_FORM_DATA, fileName);
  </code></pre>
  
  <p>The question is how can I use fluent API to realize this function.</p>
  
  <p>I find <code>.bodyFile(new File(""), ContentType.MULTIPART_FORM_DATA)</code> but I don`t know how to set the form param name of the file.</p>