To check if a value is NaN, you should use the isNaN() function

I have this code showing some error, and what I intended is to make the code do something when totalDaysFromPicker is equal to NaN , but ended up learning something.

  if (totalDaysFromPicker === 0 || totalDaysFromPicker === NaN) {
      setMessage("Please select a duration and date");
      setMessageType("error"); // Set message type to error
      setCalcBtnActive(true);
      return;
    }

What I learned:

In JavaScript, NaN is a special value that stands for “Not-a-Number.” However, comparing totalDaysFromPicker to NaN using == or === will not work as expected because NaN is not equal to anything, even itself.

To check if a value is NaN, you should use the isNaN() function. Also, the condition to check if the value is 0 can be included in the same check. Here’s how you can modify your condition:

if (totalDaysFromPicker === 0 || isNaN(totalDaysFromPicker)) {
  setMessage("Please select a duration and date");
  setMessageType("error"); // Set message type to error
  setCalcBtnActive(true);
  return;
}

Explanation:

• isNaN(totalDaysFromPicker) checks if totalDaysFromPicker is NaN.
• The condition will trigger the error message if totalDaysFromPicker is either 0 or NaN.

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