Why my code snippet in the condition still executing while the condition is not true?

Issue

          let Year = document.getElementById('year').value;
          let Month = document.getElementById('month').value;
          let date = document.getElementById("day").value;
         
          if(typeof Year !== "number" || typeof Month !== "number" || typeof date !== "number"){
            alert("Invalid Date ");
          }

I was expecting no alert as I input numeric values, but it was still displaying the alert message in the condition.

Solution

The value of Input is always string.

So, you can do like below.

let Year =document.getElementById('year').value;
let Month =document.getElementById('month').value;
let date =document.getElementById("day").value;
if(isNaN(Year+Month+date) ){
  alert("Invalid Date ");  
 
}

you need more validation like date > 0 ... but my code is enough as your code now.

I think my answer can help you.

Answered By - J.Porter