We are required to write a JavaScript program that provides the user an input to enter a string value.
The program should then check the input value against some hard-coded array values. Our program should print true to the screen if the input string value is included in the array, false otherwise.
Example
The code for this will be −
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width">
<title>CHECK EXISTENCE</title>
</head>
<body>
<script>
const arr = ['arsenal', 'chelsea', 'everton', 'fulham',
'swansea'];
const checkExistence = () => {
const userInput = document.getElementById("input").value;
const exists = arr.includes(userInput);
document.getElementById('result').innerText = exists;
};
</script>
<input type="text" id="input">
<button onclick="checkExistence()">Check</button>
<p id='result'></p>
</body>
</html>Output
And the output on the screen will be −
