javascript check if variable is nan code example
Example 1: compare NaN in javascript if condititon
// Use isNaN()
// In javascript compare NaN direct alweys return false
let num1 = Number("Vishal");
// This code never work
if(num1 == NaN){ // Direct compare NaN alweys return false so use isNaN() function
....... Your Code .......
}
// This code work
if(isNaN(num1){
.........Your Code .......
}
Example 2: javascript check if is nan
function isNaN(x) {
return x !== x;
};
isNaN(NaN);//true
Example 3: check if var is NaN
let b=1
let n=readline()
if(isNaN(b)){
console.log("You typed 0!")
}else{
console.log("You did not type 0!")
}