To fire a JavaScript function when the user finishes typing, try to run the following code −
Example
<html>
<body>
<script>
var timer = null;
$("#myText").keydown(function(){
clearTimeout(timer);
timer = setTimeout(doStuff, 1000)
});
function doStuff() {
alert("Write more!");
}
</script>
<input type = "text" id = "myText" />
</body>
</html>