jQuery form validation example
In this tutorials, we going to use jQuery
to validate the form on the client machine. jQuery
is the most popular JavaScript Library. It has many predefined methods that make the scripting much simpler.
How to use jQuery
You have two option to integrate jQuery in your project.
JS Snippet
To get the values of forms input, we have val()
method. Its return the value of input form specified by id attribute
function formValidationFn() {
// geting the values of form input
var userName = $("#uname").val();
var userEmail = $("#uemail").val();
var userPass = $("#upass").val();
// checking the condition
if (userName === null || userName === "") {
alert("Name can't be blank.");
return false;
} else if (userEmail === null || userEmail === "") {
alert("Email can't be blank.");
return false;
} else if (userPass === null || userPass === "") {
alert("Password can't be blank.");
return false;
} else {
return true;
}
}
Check the full example
<!DOCTYPE html>
<html>
<head>
<title>jQuery Form Validation Example</title>
<script src="https://code.jquery.com/jquery-3.1.1.min.js"></script>
<script type="text/javascript">
function formValidationFn() {
// geting the values of form input
var userName = $("#uname").val();
var userEmail = $("#uemail").val();
var userPass = $("#upass").val();
// checking the condition
if (userName === null || userName === "") {
alert("Name can't be blank.");
return false;
} else if (userEmail === null || userEmail === "") {
alert("Email can't be blank.");
return false;
} else if (userPass === null || userPass === "") {
alert("Password can't be blank.");
return false;
} else {
return true;
}
}
</script>
</head>
<body>
<form action="welcome.jsp" method="GET" onsubmit="return formValidationFn();">
<pre>
Name: <input type="text" id="uname" />
Email: <input type="text" id="uemail" />
Password: <input type="password" id="upass" />
<input type="submit" value="Login" />
</pre>
</form>
</body>
</html>