to call a function repeatedly every 5 seconds in JavaScript we can use the setInterval() method perform periodic evaluations of expressions or call a function.
Syntax:
setInterval(function, milliseconds, param1, param2, ...)Parameters: This function accepts the following parameters:
- function: This parameter holds the function name which to be called periodically.
- milliseconds: This parameter holds the period, in milliseconds, setInterval() calls/executes the function above.
- param1, param2, … : Some additional parameters to be passed as input parameters to function.
Return Value: This method returns the ID representing the timer set by the method. This ID can be used to clear/unset the timer by calling the clearInterval() method and passing it to this ID as a parameter.
Example: Here, the setInterval() method repeatedly evaluates an expression/calls a function. The way to clear/unset the timer set by the setInterval() method is to use the clearInterval() method and pass it the ID/value returned on calling setInterval().
<!DOCTYPE html><html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Document</title>
</head>
<body>
<p>
Click the button to start
timer, you will be alerted
every 5 seconds until you
close the window or press
the button to stop timer
</p>
<button onclick="startTimer()">
Start Timer
</button>
<button onclick="stopTimer()">
Stop Timer
</button>
<p id="gfg"></p>
<script>
let timer;
function startTimer() {
timer = setInterval(function () {
document.getElementById('gfg')
.innerHTML = " 5 seconds are up ";
}, 5000);
}
function stopTimer() {
document.getElementById('gfg')
.innerHTML = " Timer stopped ";
clearInterval(timer);
}
</script>
</body>
</html>
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Output:
How to call a function repeatedly every 5 seconds in JavaScript ?