simple javascript number game-CodePudding

substract 7 every time (starting number is 100), the first answer will be 93, i dont want user to move on until he gets the first answer right

 let answerInput = document.getElementById("inpu");
 let checkButton = document.getElementById("send");
 let answers = [];
 for(let i = 100; i>2;){
   i -= 7;
   answers.push(i);// [93, 86,...]
 }
  checkButton.onclick = function(){
    //my struggle here

    if(isNaN(answerInput.value) === true){
      answer.value = "";
      answer.placeholder = "only numbers are allowed";
     }
 }

CodePudding user response：

There is no need to store the numbers in an array, seen as the next number is always 7 from the last, just keep a counter for the number. And then just compare this to the input - 7;

eg.

const span = document.querySelector('span');
const input = document.querySelector('input');
const button = document.querySelector('button');

let number = 100;

const showNum = () => span.innerText = number;

showNum();

button.addEventListener('click', () => {
  const want = number - 7;
  if (Number(input.value) === want) {
    if (want == 2) {
      alert("Well done you..");
    } else {
      number -= 7;
      showNum();
    }
  }
});

Subtract 7 from <span></span> = <input type="number" value="100"/><button>Try</button>

CodePudding user response：

Solution:

let answerInput = document.getElementById("inpu");
let checkButton = document.getElementById("send");
let answers = [];
for (let i = 100; i > 2; ) {
  i -= 7;
  answers.push(i); // [93, 86,...]
}
checkButton.onclick = function () {
  if (isNaN(answerInput.value) === true) {
    answer.value = "";
    answer.placeholder = "only numbers are allowed";
  }
  // check if answer correct, `!=` compare with type coercion
  else if (answerInput.value != answers[0]) {
    answer.placeholder = "try again"
  }
  else {
    answers.shift(); // remove first array element
    answer.placeholder = "correct!"
  }
};

<!DOCTYPE html>
<html>
<head></head>
<body>
  <!--
    You can use type="number" to auto-avoid letters in field:
    <input id=inpu type="number" />
  -->
  <input id=inpu />
  <input disabled id=answer />
  <button id=send>Send</button>
</body>
</html>