Issue with my conditional statements

Beat me too it, I should refresh my old browser tabs before answering questions haha. But good example that there's always more than one way to solve a problem.

Don't worry, I've certainly made my share of lengthy answers that ends up being posted a while after the question was answered as well .

And yeah there definitively are many varied ways of solving the same issue. That's part of the reason why I personally don't mind it when multiple people end up answering the same question. Different people often come up with slightly different solutions, and that can be helpful and educational on it's own.

Thanks for the feedback guys. Benjamin Larson that explanation makes a lot of sense. I was overthinking because initially i thought about starting the condition with if (pin.length === 4 || pin.length === 6)and have it return true but once i noticed the program didn't seem to consider the second conditional statement i figured id start with something false so that the program could keep looking through the conditional until it returned true.

andren
Taking into consideration both of you guys feedback this is what i came with to finalize it and also address the fact that the program needs to check whether the pin entirely consists of numbers However when i type a pin that contains characters other than digits like ('a234') or ('.234') it returns true instead of false for these scenarios. Any thoughts ?

function validatePIN(pin){ 
  if (pin.length === 4 || pin.length === 6) {
    return true;
   }
  else if( isNaN(pin)===true) {
   return false;
   } 
   else {
     return false;
   } 
} 

Amir Bizimana If statements are evaluated from top to bottom, and else if and else statements only run if the first if statement evaluates to false.

Since "a234" does have a length of 4 the first if statement will run, which means that the else if is not executed at all. And even if that was not the case, once you return a value the method stops executing, so even if you didn't use if/else if statements the method would stop once the if statement ran anyway.

The solution to that issue is pretty simple, move the isNaN check to the top. Like this

function validatePIN(pin){ 
  if(isNaN(pin)) {
    return false;
  } 
  else if (pin.length === 4 || pin.length === 6) {
    return true;
  }
  else {
    return false;
  } 
} 

Also since isNaN returns true of false on its own you don't need to compare it to true, that is redundant. So I removed that comparison.

Edit:

You could also make the if statement more compact by combining the if and else if into one check like this:

function validatePIN(pin){ 
   if ((pin.length === 4 || pin.length === 6) && !isNaN(pin)) {
     return true;
   }
   else {
     return false;
   } 
} 

That is a bit more complicated to read, but it essentially says "if pin is 4 or 6 and it's not not a number then return true". I had to wrap the first two conditionals in parentheses to make sure they are evaluated first.

I do most of my programming in C#, Java and PHP so I'll have to think about this one, but even with andren's improved function, there are still exceptions such as:

validatePIN("1.23");

Are there any other JavaScript functions that could check this without using Regular Expressions? +1 to strongly typed languages that don't have this problem haha

Benjamin Larson Ops, you are right. I forgot to use . when testing the code. The simplest (but somewhat lazy and hacky) way to solve that issue would just be to explicitly check for the dot like this:

function validatePIN(pin){ 
   if ((pin.length === 4 || pin.length === 6) && !isNaN(pin) && !pin.includes(".")) {
     return true;
   }
   else {
     return false;
   } 
} 

That works, but it's admittedly not very elegant. I spend a decent amount of time coding in JavaScript (though I prefer to use TypeScript whenever i can get away with it) but I can't say I deal with number input validation all that often, so I don't have any good elegant solution I can think of at the top of my head.

I also tend to prefer strongly typed languages. Auto conversions might be nice for people just starting out with programming but they become a pain to deal with later.

Yeah, I tried a different way, which requires the input be entered as an integer and not a string.

function validatePIN(pin){ 
   if (Number.isInteger(pin) && (pin.toString().length === 4 || pin.toString().length === 6)) {
     return true;
   }
   else {
     return false;
   } 
}

Searching for the "." is better than mine because Number.isInteger() isn't supported in older versions of IE. There's probably validation packages out there that do this much better and if you're really ambitious Amir, you can learn Regular Expressions to have a lot more control in these situations.

Im gonna get some learning done on those. Thanks for posting the MDN resources !

I hate to be "that guy", but I can technically break that one with:

validatePIN("1234.0")

Sorry...lol