title: Adding days to date in Angular is not working properly
body: <p>I am trying to add 12 days to a specific date. but I am getting the new date as not expected.
  Here is my code</p>
  <pre><code>addDays(days: number): any {
      let startDate = new Date(this.selectedDeliveryDate);
      let endDate = new Date();
      endDate = new Date(startDate.setDate(startDate.getDate() + days))
      console.log(startDate, endDate, days)
  }
  </code></pre>
  <p><code>this.selectedDeliveryDate = Wed Dec 08 2021 05:30:00 GMT+0530 (India Standard Time)</code> and
  <code>days = 12</code>
  I am getting the <code>endDate</code> as <code>Tue Feb 20 2024 17:49:13 GMT+0530 (India Standard Time)</code></p>
  <p><strong>EDIT</strong>
  I have printed the following code to test</p>
  <pre><code>console.log((startDate.getDate() + days));
  </code></pre>
  <p>and selected <code>07-12-2021</code> as <code>start date</code> and <code>days</code> is <code>12</code>. I am getting the result like <code>712</code>. Its just appending the number of days to the day.</p>