title: typescript - convert string to number
body: <pre><code>totalbalancetemp = (Number(this.balance)) + (Number(this.pastAmount));
  </code></pre>
  
  <p>My <code>totalbalancetemp</code> is returning undefined whereas <code>this.balance</code> is equal to 34 and <code>this.pastAmount</code> is equal to 23.</p>
  
  <p>I have this in controller and displaying <code>totalbalancetemp</code> using exp in html</p>