Definition and Usage Timing Events..
The window object allows execution of code at specified time intervals.
These time intervals are called timing events.
The two key methods to use with JavaScript are:
setTimeout(function, milliseconds)
Executes a function, after waiting a specified number of milliseconds.
setInterval(function, milliseconds)
Same as setTimeout(), but repeats the execution of the function continuously.
The setTimeout() and setInterval() are both methods of the HTML DOM Window object.
The setTimeout() Method
Syntax : window.setTimeout(function, milliseconds);
The window.setTimeout() method can be written without the window prefix.
The first parameter is a function to be executed.
The second parameter indicates the number of milliseconds before execution.
How to Stop the Execution?
The clearTimeout() method stops the execution of the function specified in setTimeout().
window.clearTimeout(timeoutVariable)
The window.clearTimeout() method can be written without the window prefix.
The clearTimeout() method uses the variable returned from setTimeout():
myVar = setTimeout(function, milliseconds);
clearTimeout(myVar);
If the function has not already been executed, you can stop the execution by calling the clearTimeout() method:
The setInterval() Method
The setInterval() method repeats a given function at every given time-interval.
window.setInterval(function, milliseconds);
The window.setInterval() method can be written without the window prefix.
The first parameter is the function to be executed.
The second parameter indicates the length of the time-interval between each execution.
This example executes a function called "myTimer" once every second (like a digital watch).
How to Stop the Execution?
The clearInterval() method stops the executions of the function specified in the setInterval() method.
window.clearInterval(timerVariable)
The window.clearInterval() method can be written without the window prefix.
The clearInterval() method uses the variable returned from setInterval():
myVar = setInterval(function, milliseconds);
clearInterval(myVar);
CODING:The window object allows execution of code at specified time intervals.
These time intervals are called timing events.
The two key methods to use with JavaScript are:
setTimeout(function, milliseconds)
Executes a function, after waiting a specified number of milliseconds.
setInterval(function, milliseconds)
Same as setTimeout(), but repeats the execution of the function continuously.
The setTimeout() and setInterval() are both methods of the HTML DOM Window object.
The setTimeout() Method
Syntax : window.setTimeout(function, milliseconds);
The window.setTimeout() method can be written without the window prefix.
The first parameter is a function to be executed.
The second parameter indicates the number of milliseconds before execution.
How to Stop the Execution?
The clearTimeout() method stops the execution of the function specified in setTimeout().
window.clearTimeout(timeoutVariable)
The window.clearTimeout() method can be written without the window prefix.
The clearTimeout() method uses the variable returned from setTimeout():
myVar = setTimeout(function, milliseconds);
clearTimeout(myVar);
If the function has not already been executed, you can stop the execution by calling the clearTimeout() method:
The setInterval() Method
The setInterval() method repeats a given function at every given time-interval.
window.setInterval(function, milliseconds);
The window.setInterval() method can be written without the window prefix.
The first parameter is the function to be executed.
The second parameter indicates the length of the time-interval between each execution.
This example executes a function called "myTimer" once every second (like a digital watch).
How to Stop the Execution?
The clearInterval() method stops the executions of the function specified in the setInterval() method.
window.clearInterval(timerVariable)
The window.clearInterval() method can be written without the window prefix.
The clearInterval() method uses the variable returned from setInterval():
myVar = setInterval(function, milliseconds);
clearInterval(myVar);
<!DOCTYPE html>
<html>
<body>
<p>Click button Wait 2 seconds. The page will alert "Hello".</p>
<p>Click "Stop" to prevent the first function to execute.</p>
<p>(You must click "Stop" before the 2 seconds are up.)</p>
<button onclick="myVar = setTimeout(myFunction, 2000)">Start 2 seconds</button>
<button onclick="clearTimeout(myVar)">Stop it</button>
<h1 id="time"></h1>
<button onclick="x = setInterval(myTimer ,1000);">Start</button>
<button onclick="clearTimeout(x)">Stop it</button>
<script>
function myFunction() {
alert("Finish 2 seconds");
}
function myTimer() {
var t = new Date();
document.getElementById("time").innerHTML = t.toLocaleTimeString();
}
</script>
</body>
</html>
<html>
<body>
<p>Click button Wait 2 seconds. The page will alert "Hello".</p>
<p>Click "Stop" to prevent the first function to execute.</p>
<p>(You must click "Stop" before the 2 seconds are up.)</p>
<button onclick="myVar = setTimeout(myFunction, 2000)">Start 2 seconds</button>
<button onclick="clearTimeout(myVar)">Stop it</button>
<h1 id="time"></h1>
<button onclick="x = setInterval(myTimer ,1000);">Start</button>
<button onclick="clearTimeout(x)">Stop it</button>
<script>
function myFunction() {
alert("Finish 2 seconds");
}
function myTimer() {
var t = new Date();
document.getElementById("time").innerHTML = t.toLocaleTimeString();
}
</script>
</body>
</html>
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