code-boxx/0-JS-EVERY-SEC.MD

## 0-JS-EVERY-SEC.MD

      
    Raw
  

              0-JS-EVERY-SEC.MD
            
          
    RUN JAVASCRIPT EVERY SECOND

https://code-boxx.com/run-javascript-every-second/
LICENSE

Copyright by Code Boxx
Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.

  
## 1-set-interval.html
<!DOCTYPE html>
<html>
  <head>
    <title>JS Every Second - Set Interval</title>
  </head>
  <body>
    <!-- (A) CURRENT TIME WILL BE SHOWN HERE -->
    <div id="timeNow"></div>

    <script>
    // (B) RUN THIS FUNCTION EVERY SECOND TO UPDATE HTML
    var showTime = () => {
      let now  = new Date(),
          hr = now.getHours(), min = now.getMinutes(), sec = now.getSeconds();
      document.getElementById("timeNow").innerHTML = `${hr}:${min}:${sec}`;
    };

    // (C) START INTERVAL
    var timer = setInterval(showTime, 1000);
    // TO STOP - clearInterval(timer);
    </script>
  </body>
</html>

## 2-recursive.html
<!DOCTYPE html>
<html>
  <head>
    <title>JS Every Second - Recursive Timeout</title>
  </head>
  <body>
    <!-- (A) CURRENT TIME WILL BE SHOWN HERE -->
    <div id="timeNow"></div>

    <script>
    // (B) RUN THIS FUNCTION EVERY SECOND TO UPDATE HTML
    var showTime = () => {
      // (B1) UPDATE HTML
      let now  = new Date(),
          hr = now.getHours(), min = now.getMinutes(), sec = now.getSeconds();
      document.getElementById("timeNow").innerHTML = `${hr}:${min}:${sec}`;

      // (B2) LOOP
      timer = setTimeout(showTime, 1000);
    };

    // (C) START!
    var timer = setTimeout(showTime, 0);
    // TO STOP - clearTimeout(timer);
    </script>
  </body>
</html>

## 3-async-loop.html
<!DOCTYPE html>
<html>
  <head>
    <title>JS Every Second - Looping Async Function</title>
  </head>
  <body>
    <!-- (A) CURRENT TIME WILL BE SHOWN HERE -->
    <div id="timeNow"></div>

    <script>
    // (B) RUN THIS FUNCTION EVERY SECOND TO UPDATE HTML
    var showTime = async () => { while (true) {
      // (B1) UPDATE CURRENT TIME
      let now  = new Date(),
          hr = now.getHours(), min = now.getMinutes(), sec = now.getSeconds();
      document.getElementById("timeNow").innerHTML = `${hr}:${min}:${sec}`;

      // (B2) WAIT FOR 1 SECOND
      await new Promise(resolve => setTimeout(resolve, 1000));
    }};

    // (C) START!
    showTime();
    </script>
  </body>
</html>
	<!DOCTYPE html>
	<html>
	<head>
	<title>JS Every Second - Set Interval</title>
	</head>
	<body>
	<!-- (A) CURRENT TIME WILL BE SHOWN HERE -->
	<div id="timeNow"></div>

	<script>
	// (B) RUN THIS FUNCTION EVERY SECOND TO UPDATE HTML
	var showTime = () => {
	let now = new Date(),
	hr = now.getHours(), min = now.getMinutes(), sec = now.getSeconds();
	document.getElementById("timeNow").innerHTML = `${hr}:${min}:${sec}`;
	};

	// (C) START INTERVAL
	var timer = setInterval(showTime, 1000);
	// TO STOP - clearInterval(timer);
	</script>
	</body>
	</html>