Using getElementById attribute you can Pass JavaScript variable to HTML input value.
Input box
<input type="text" id="mytext">
JavaScript code
document.getElementById("mytext").value = msg;
Pass variable to HTML input value using JavaScript
Simple example code.
<!DOCTYPE html>
<html>
<body>
<input type="text" id="mytext">
<script type="text/javascript">
var msg = "Hello World!";
document.getElementById("mytext").value = msg;
</script>
</body>
</html>
Output:
Do comment if you have any doubts or suggestions on this JS variable topic.
Note: The All JS Examples codes are tested on the Firefox browser and the Chrome browser.
OS: Windows 10
Code: HTML 5 Version
very nice post