JavaScript Program to Change Color of Textbox if Empty String Submitted

JavaScript Program to Change Color of Textbox if Empty String Submitted

JavaScript Program to Change Color of Textbox if Empty String Submitted

Write a JavaScript program to change color of textbox if empty string submitted.

Source Code

<html>
<head>
<title>Change Color of Textbox if Empty String Submitted</title>
<script>
function fun()
{
	txt = document.getElementById('t1').value
	if(txt.length == 0)
	    document.getElementById('t1').style.borderColor = "red"
}
</script>
</head>
<body>
    <input type="text" id="t1">
    <input type="button" value="Submit" onclick="fun()">
</body>
</html>

Output