Javascript DOM oninvalid Event check number value

Introduction

Alert some text if an input field contains a number that is less than 2 or greater than 5:

If you submit the form with a number that is less than 2 or greater than 5, an alert message will occur.

The oninvalid event is not supported in Internet Explorer 9 and earlier or Safari.

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<!DOCTYPE html>
<html>
<body>
<form action="/action_page.php" method="get">
  Pick a number between 2 and 5: 
  <input type="number" 
         id="myInput" 
         name="quantity" 
         min="2" 
         max="5" 
         required>
  <input type="submit" value="Submit">
</form>//from w w  w .  ja va 2s.c  o  m

<p id="demo"></p>
<script>
document.getElementById("myInput").addEventListener("invalid", myFunction);

function myFunction() {
  document.getElementById("demo").innerHTML = "You must pick a number between 2 and 5. You chose: " + this.value;
}
</script>

</body>
</html>



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