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JavaScript JavaScript Foundations Numbers Parsing Numbers From Strings

Posted by MUZ140252 Prudence Khupe
MUZ140252 Prudence Khupe
8,921 Points

parse code

failing to extract numbers using the parse

index.html 
<!DOCTYPE html>
<html lang="en">
  <head>
    <title>JavaScript Foundations: Parsing Numbers From Strings</title>
    <link rel="stylesheet" href="core.css">
    <script>
      var boxWidth = "640px";
      var boxHeight = "480px";
      var numWidth = parseInt("640px", 10)


    </script>
  </head>
  <body>
    <h1>JavaScript Foundations</h1>
    <h2>Parsing Numbers From Strings</h2>
    <script src="viewer.js"></script>
  </body>
</html>

2 Answers

Marcus Parsons
Marcus Parsons
15,719 Points
Marcus Parsons
Marcus Parsons
15,719 Points

Hey Prudence Khupe,

It wants you to use the variable instead of the actual value because a lot of times those variables will be dynamically generated by some other part of the program. So, instead of putting the value of boxWidth into parseInt, put the variable name like so:

      var boxWidth = "640px";
      var boxHeight = "480px";
      var numWidth = parseInt(boxWidth, 10);

This way if boxWidth were to change we would get the value of boxWidth. I hope that makes sense! :)

Salman Akram
PLUS
Salman Akram
Courses Plus Student 40,065 Points
Salman Akram
Salman Akram
Courses Plus Student 40,065 Points

Hi Prudence,

Just swap out the number - "640px" to replace it with variable name boxWidth, we need to extract the number from the boxWidth's variable, not string or number. 

  var numWidth = parseInt("640px", 10)

Hope that helps.