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JavaScript JavaScript Foundations Numbers Parsing Numbers From Strings

Posted by Daniel Deng
Daniel Deng
Courses Plus Student 4,322 Points

JavaScript problem

var boxWidth = "640px"; var a = boxWidth.substr(0, 3); var numWidth = parseInt(a, 10);

  var boxHeight = "480px";
  var b = boxHeight.substr(0, 3);
  var numHeight = parseInt(b, 10);

Always get this error message: Bummer! Sorry! That's not correct. A correct answer will use the form: var numVariable = parseInt(stringVariable, radix);

However the above code can execute correctly. Anybody knows what's going-on?

1 Answer

Stone Preston
Stone Preston
42,016 Points
Stone Preston
Stone Preston
42,016 Points

you dont need to use substrings. parseInt ignores any characters that are not numerals in the specified radix. see this documentation for more info.

 <script>
      var boxWidth = "640px";
      var boxHeight = "480px";
      var numWidth = parseInt(boxWidth, 10);
      var numHeight = parseInt(boxHeight, 10);



    </script>
Daniel Deng
Daniel Deng
Courses Plus Student 4,322 Points

I see, thanks.