I have a Rails web app (Online Examination System). I have disabled Right click, selection, copy etc using JavaScript in the examination interface. So, I want my app to detect whether JavaScript is enabled on interface start up. I have checked it by using <noscript> tag as follows.
<noscript>
<meta http-equiv="refresh" content="5">
<div id="noscript_message" style="color: white; background-color: red;">
It is detected that Javascript is turned off in your web brower. Please turn it on to load the page correctly. For more reference about how to turn it on, please refer <a href="http://www.enable-javascript.com/" target="_blank">
instructions how to enable JavaScript in your web browser</a>.
</div>
</noscript>
But I could only detect and show up a message as warning. My intention is not to load that page and show up the warning message only. How that can be achieved?
Thanks :)-
You could use no-js class on your body element and hide it with CSS, then show it with JavaScript so if users have JS disabled they get an "empty" page.
<body class="no-js">
In CSS:
body.no-js { display: none; }
Then in JS:
document.body.className = "";
来源：https://stackoverflow.com/questions/15807305/stop-loading-the-page-if-javascript-is-disabled