HTML Code

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <title>isInteger — parse</title>
</head>
<body>
  <h1>Parse then check</h1>
  <pre id="out"></pre>
  <script src="https://cdn.jsdelivr.net/npm/lodash@4.17.21/lodash.min.js"></script>
  <script>
    function asInteger(input) {
      var n = Number(input);
      return _.isInteger(n) ? n : null;
    }
    document.getElementById("out").textContent =
      asInteger("42") + "\n" +
      asInteger("3.5") + "\n" +
      asInteger("oops");
  </script>
</body>
</html>

Lines: 0 | Characters: 0

Live Preview Auto-refresh on Run

Lodash _.isInteger — parse (Try It)