title: Angular 6: error TS2339: Property 'value' does not exist on type 'HTMLElement'
body: <p>I have textarea which allow user to submit comments, I want to grab the date on time the comment is submitted, and save to json together with comment added :</p>
  
  <p>after comment is submitted in json file I would like to have something like this:</p>
  
  <pre><code> "comment": [
      {
        "id": 1,
        "username": "Michael Ross",
        "city": "New York USA",
        "date": "2018-01-01T00:00:00",
        "task_id": 1,
        "description": "Lorem ipsum dolor sit amet enim. Etiam ullamcorper. Suspendisse a pellentesque dui, non felis. Maecenas malesuada elit lectus felis, malesuada ultricies. Curabitur et lig"
      }
  ]
  </code></pre>
  
  <p>Problem: Right now when comment is submitted I have the following: no date is displayed:</p>
  
  <pre><code> "comment": [
      {
        "id": 1,
        "username": "Michael Ross",
        "city": "New York USA",
        "task_id": 1,
        "description": "Lorem ipsum dolor sit amet enim. Etiam ullamcorper. Suspendisse a pellentesque dui, non felis. Maecenas malesuada elit lectus felis, malesuada ultricies. Curabitur et lig"
      }
  ]
  </code></pre>
  
  <p>Here is what I have tried so far to grab the date from entered comment.</p>
  
  <p>HTML :</p>
  
  <pre><code>&lt;form class="add-comments" [formGroup]="addForm" (keyup.enter)="addComments()"&gt;
        &lt;input type="hidden" id="localTime" name="localTime"&gt;
      &lt;div class="form-group"&gt;
        &lt;textarea class="form-control" rows="1" placeholder="Add comments" formControlName="description" id="description"&gt;&lt;/textarea&gt;
      &lt;/div&gt;
    &lt;/form&gt;
  </code></pre>
  
  <p>Here is method on compoents ts.</p>
  
  <pre><code> addComments(task_id) {
      const formData = this.addForm.value;
      formData.task_id = task_id;
      this.userService.addComments(formData)
      .subscribe(data =&gt; {
        this.comments.push(this.addForm.value);
      });
      const date = new Date();
      const d = date.getUTCDate();
      const day = (d &lt; 10) ? '0' + d : d;
      const m = date.getUTCMonth() + 1;
      const month = (m &lt; 10) ? '0' + m : m;
      const year = date.getUTCFullYear();
      const h = date.getUTCHours();
      const hour = (h &lt; 10) ? '0' + h : h;
      const mi = date.getUTCMinutes();
      const minute = (mi &lt; 10) ? '0' + mi : mi;
      const sc = date.getUTCSeconds();
      const second = (sc &lt; 10) ? '0' + sc : sc;
      const loctime = month + day + hour + minute + year + '.' + second;
  
      document.getElementById('localTime').value = loctime;
  
    }
  </code></pre>
  
  <p>Unfortunatelly when I submit the comment , I get the following error</p>
  
  <pre><code>ERROR in src/app/user-profile/user-profile.component.ts(75,21): error TS2365: Operator '+' cannot be applied to types 'string | number' and 'string | number'.
  src/app/user-profile/user-profile.component.ts(77,42): error TS2339: Property 'value' does not exist on type 'HTMLElement'.
  </code></pre>
  
  <p>what do I need to change to get what I want??</p>