username validation

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showing results for - "username validation"

12 Apr 2019

1<html>
2<head>
3	<title></title>
4</head>
5<body>
6<form method="post" action="">
7	username:<input type="text"  id="name" onkeyup="validation()">
8	</form>
9</body>
10<script type="text/javascript">
11	function validation(){
12	var username=document.getElementById("name").value;///get id with value 
13	var usernamepattern=/^[A-Za-z .]{3,15}$/;////Regular expression
14	if(usernamepattern.test(username))
15	{
16		document.getElementById("name").style.backgroundColor='yellow';
17    }
18    else
19    {
20    	document.getElementById("name").style.backgroundColor='red'; }
21	}
22
23</script>
24</html>

source

Charlotte

09 Feb 2016

1
2            
3                
4            
5         const checkUsername = () => {
6
7    let valid = false;
8    const min = 3,
9        max = 25;
10    const username = usernameEl.value.trim();
11
12    if (!isRequired(username)) {
13        showError(usernameEl, 'Username cannot be blank.');
14    } else if (!isBetween(username.length, min, max)) {
15        showError(usernameEl, `Username must be between ${min} and ${max} characters.`)
16    } else {
17        showSuccess(usernameEl);
18        valid = true;
19    }
20    return valid;
21}Code language: JavaScript (javascript)