soldni/type-check-js-demo.html

## type-check-js-demo.html
<!DOCTYPE html>
<html>
<head>
    <title>Type check demo</title>
</head>
<body>

<form>
Insert only digit here<br>
<input id="digitsInput" type="text" name="digits" onblur="checkdigits()">
<input type="submit" value="Go">
</form>

<script type="text/javascript">
function isNumber(n) {
    // returns True if n is a number, False otherwise
    // source: http://stackoverflow.com/a/1830844/938048
    return !isNaN(parseFloat(n)) && isFinite(n);
}

function checkdigits () {
    // get element with digits
    digitsInput = document.getElementById("digitsInput");

    // check if inupt is invalid and if input has length greater than 0
    if (!isNumber(digitsInput.value) && digitsInput.value.length > 0) {
        // show a pop-up
        alert('Please insert number only!');

        // clear input
        digitsInput.value = '';
    };
}
</script>

</body>
</html>
	<!DOCTYPE html>
	<html>
	<head>
	<title>Type check demo</title>
	</head>
	<body>

	<form>
	Insert only digit here<br>
	<input id="digitsInput" type="text" name="digits" onblur="checkdigits()">
	<input type="submit" value="Go">
	</form>

	<script type="text/javascript">
	function isNumber(n) {
	// returns True if n is a number, False otherwise
	// source: http://stackoverflow.com/a/1830844/938048
	return !isNaN(parseFloat(n)) && isFinite(n);
	}

	function checkdigits () {
	// get element with digits
	digitsInput = document.getElementById("digitsInput");

	// check if inupt is invalid and if input has length greater than 0
	if (!isNumber(digitsInput.value) && digitsInput.value.length > 0) {
	// show a pop-up
	alert('Please insert number only!');

	// clear input
	digitsInput.value = '';
	};
	}
	</script>

	</body>
	</html>