How to Check for Numeric Values in JavaScript Without Libraries?

Checking Numerics in Pure JavaScript

Determining if a value represents a number in pure JavaScript raises the question of whether there exists an equivalent to jQuery's isNumeric(). Although jQuery provides such a function, pure JavaScript lacks an inherent counterpart.

However, with a custom function, you can replicate this functionality:

<code class="javascript">function isNumeric(n) {
  return !isNaN(parseFloat(n)) && isFinite(n);
}</code>

This function utilizes parseFloat() to convert the input to a floating-point number and then checks if it's a finite value using isFinite() to handle special cases like NaN and Infinity.

Note: Avoid using parseInt() for numeric checks, as it can return non-numeric values.

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