A demo of checkbox checked with JavaScript

The Code
Output
<!DOCTYPE html>
<html>
<head>

 <link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.5/css/bootstrap.min.css">

<style>
.divcls
{
width:200px;
height: 80px;
padding:20px;
background-color:#4D9999;
color:#fff;
font-size:15px;
}

</style>
</head>

<body>

<div class="divcls"><input type="checkbox" checked id="demochecked"/>Show/Hide button</div>
<br />
      
        <div class="col-sm-offset-2 col-sm-5" id="chkboxdemo">   
        <p><input type="submit" class="btn btn-lg btn-danger" value="Save Information"></p>
        </div>

 
<script>
var chkstatus = document.getElementById('demochecked');
var btnshowhide = document.getElementById('chkboxdemo');


chkstatus.onchange = function() {
    
    btnshowhide.hidden = this.checked ? false : true;
};

</script>
</body>
</html>
Show/Hide button