I’m building a decimal-to-binary number convertor. I need to check if the value returned by the parseInt() function is a number or not. I know that you can use the isNaN() function. This function takes in a string or number as an argument and returns true if it evaluates to NaN. I need the second condition in my if statement to use the isNaN() function to check if the value returned by parseInt() is NaN. I also want to consider only positive numbers to convert, I want to add a third condition in the if statement to check whether the number is less than 0.

This is my code so far

   const numberInput = document.getElementById("number-input");
   const convertBtn = document.getElementById("convert-btn");
   const result = document.getElementById("result");

   const checkUserInput = () = {
   if (!numberInput.value || isNaN(parseInt(numberInput.value))) {

   }

   console.log(numberInput.value);
   };

   convertBtn.addEventListener("click", checkUserInput);

   numberInput.addEventListener("keydown", (e) = {
   if (e.key === "Enter") {
      checkUserInput();
    }
  });

This is the part I’m talking about. I tried this

I think this might be correct, let me know if someone has something better.

 if (!numberInput.value || isNaN(parseInt(numberInput.value)) || parseInt(numberInput.value) < 0) {

        }

     const checkUserInput = () = {
        if (!numberInput.value || isNaN(parseInt(numberInput.value))) {

        }