title: How to get the input value written by interpolation code using Reactive Forms?
body: <p>In this case i'm using Reactive Forms not ngModel</p>
  
  <p>I'm writting an interpolation value into an input text field</p>
  
  <p>When i submit my form i get all the  field values, except the interpolated one.
  The interpolated is empty</p>
  
  <p>How to fix it??</p>
  
  <pre><code>&lt;label class="form-control-sm"
           id="identificationCode"
           name="identificationCode"&gt;{{reference.value + "-" + publishDate.value}}
  &lt;/label&gt;
  &lt;input  #txtIdCode
           type="text" 
           id="idCode" 
           name="idCode"
           formControlName="txtIdCode"
           maxlength="15"                     
           value="{{reference.value + '-' + publishDate.value}}"&gt;
  </code></pre>
  
  <p>When i get txtIdCode in this way, i get an empty value but the input text is filled:</p>
  
  <pre><code>item.identificationCode = this.myForm.controls["txtIdCode"].value;
  </code></pre>