wellercs/js_DataErrorMessage

## js_DataErrorMessage
<html>
        <head>
                <title>Data Error Message Sandbox</title>
                <script type="text/javascript">
                function checkForm() {
                        var myformelement = document.getElementById('myformelement');
                        var usermessage = document.getElementById('usermessage');
                        if (myformelement.value == "") {
                                try {
                                        alert(myformelement.dataset.errorMessage);
                                        usermessage.innerHTML = "dataset";
                                }
                                catch(err) {
                                        try {
                                                alert(myformelement.getAttribute('data-error-message'));
                                                usermessage.innerHTML = "getAttribute";
                                        }
                                        catch(err) {
                                                alert("Invalid data");
                                                usermessage.innerHTML = "basicAlert";
                                        }
                                }
                                return false;
                        }
                        else {
                                return true;
                        }
                }
                </script>
        </head>
        <body>
                <div id="usermessage"></div>
                <form id="myform" name="myform" method="post" action="" onsubmit="return checkForm();">
                        <label for="myformelement">My Form Element</label>
                        <input type="text" id="myformelement" name="myformelement" value="" data-error-message="Invaid data in 'My Form Element'" />
                        <input type="submit" id="btnsubmit" name="btnsubmit" value="Submit" />
                </form>
        </body>
</html>
	<html>
	<head>
	<title>Data Error Message Sandbox</title>
	<script type="text/javascript">
	function checkForm() {
	var myformelement = document.getElementById('myformelement');
	var usermessage = document.getElementById('usermessage');
	if (myformelement.value == "") {
	try {
	alert(myformelement.dataset.errorMessage);
	usermessage.innerHTML = "dataset";
	}
	catch(err) {
	try {
	alert(myformelement.getAttribute('data-error-message'));
	usermessage.innerHTML = "getAttribute";
	}
	catch(err) {
	alert("Invalid data");
	usermessage.innerHTML = "basicAlert";
	}
	}
	return false;
	}
	else {
	return true;
	}
	}
	</script>
	</head>
	<body>
	<div id="usermessage"></div>
	<form id="myform" name="myform" method="post" action="" onsubmit="return checkForm();">
	<label for="myformelement">My Form Element</label>
	<input type="text" id="myformelement" name="myformelement" value="" data-error-message="Invaid data in 'My Form Element'" />
	<input type="submit" id="btnsubmit" name="btnsubmit" value="Submit" />
	</form>
	</body>
	</html>