title: Convert String to Number with Format
body: <p>I was wondering if there is an existing method to convert a formatted number String to number, such as "123,456.78" to 123456.78</p>
  
  <p>Basically, unlike DecimalFormat function, which turns a double variable to a String following that a given format such as "###,###.##" pattern. I want to implement a reverse of this functionality, which turns a String with "###,###.##" format to a double. Is there APIs to do this?</p>
  
  <p>Thank you.</p>