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JavaScript JavaScript Loops, Arrays and Objects Tracking Multiple Items with Arrays Useful Array Methods

Posted by Alejandro Galiano
Alejandro Galiano
6,613 Points

I did it with a "do/while loop" and it works. Can you check if this is correct in terms of best practices?

Hi all! I tried to write the program before watching the whole video and its final solution. I just wanted to share with you the code and to check if someone more expert could tell me if it is as valid as the final solution in terms of DRY, understanding the program, syntax, etc. 

var inStock = [ 'apples', 'eggs', 'milk', 'cookies', 'cheese', 'bread', 'lettuce', 'carrot', 'broccoli', 'pizza', 'potato', 'crackers', 'onion', 'tofu', 'frozen dinner', 'cucumber'];
var search;

function print(message) {
  document.write( '<p>' + message + '</p>');
}

do {
  search = prompt("Hi! Search for a single product in our store").toLowerCase();
  if(search === "list"){
  print(inStock.join(", "));
  } else if (search === inStock[inStock.indexOf(search)]){
    print("Yes, we have " + search + " in our store.");
  } else if (search !== "quit") {
  print(search + " is not in stock.");
  }
} while (search !== "quit")

Many thanks in advance.

AG

1 Answer

Shreyash Agarwal
Shreyash Agarwal
9,843 Points
Shreyash Agarwal
Shreyash Agarwal
9,843 Points

This is actually better practice, speaking from my programming experience.

Do while ensures that the loop runs atleast one according to syntax. The same can be done using a while() loop, however that requires the existing variable inside the evaluation to evaulate to true, before it runs the loop.

As far as user based interactions are concerned when you really WANT something to happen for sure at least once, use a do while. In short, kudos! You were spot on to do that!

Alejandro Galiano
Alejandro Galiano
6,613 Points

Thanks for your answer Shreyash!