javascript required field code example
Example 1: javascript add required attribute to input
element.setAttribute("required", ""); //turns required on
element.required = true; //turns required on through reflected attribute
jQuery(element).attr('required', ''); //turns required on
$("#elementId").attr('required', ''); //turns required on
element.removeAttribute("required"); //turns required off
element.required = false; //turns required off through reflected attribute
jQuery(element).removeAttr('required'); //turns required off
$("#elementId").removeAttr('required'); //turns required off
if (edName.hasAttribute("required")) { } //check if required
if (edName.required) { } //check if required using reflected attribute
Example 2: javascript add required to input
element.setAttribute("required", "");
element.removeAttribute("required");
Example 3: javascript onsubmit form validation
//form.html
<!DOCTYPE html>
<html>
<head>
<title>Javascript Onsubmit Event Example</title>
<link href="css/style.css" rel="stylesheet">
<script src="js/onsubmit_event.js"></script>
</head>
<body>
<div class="container">
<div class="main">
<form action="#" method="post" onsubmit="return ValidationEvent()">
<h2>Javascript Onsubmit Event Example</h2>
<label>Name :</label>
<input id="name" name="name" placeholder="Name" type="text">
<label>Email :</label>
<input id="email" name="email" placeholder="Valid Email" type="text">
<label>Gender :</label>
<input id="male" name="gender" type="radio" value="Male">
<label>Male</label>
<input id="female" name="gender" type="radio" value="Female">
<label>Female</label>
<label>Contact No. :</label>
<input id="contact" name="contact" placeholder="Contact No." type="text">
<input type="submit" value="Submit">
<span>All type of validation will execute on OnSubmit Event.</span>
</form>
</div>
</div>
</body>
</html>
//js/onsubmit_event.js
// Below Function Executes On Form Submit
function ValidationEvent() {
// Storing Field Values In Variables
var name = document.getElementById("name").value;
var email = document.getElementById("email").value;
var contact = document.getElementById("contact").value;
// Regular Expression For Email
var emailReg = /^([w-.]+@([w-]+.)+[w-]{2,4})?$/;
// Conditions
if (name != '' && email != '' && contact != '') {
if (email.match(emailReg)) {
if (document.getElementById("male").checked || document.getElementById("female").checked) {
if (contact.length == 10) {
alert("All type of validation has done on OnSubmit event.");
return true;
} else {
alert("The Contact No. must be at least 10 digit long!");
return false;
}
} else {
alert("You must select gender.....!");
return false;
}
} else {
alert("Invalid Email Address...!!!");
return false;
}
} else {
alert("All fields are required.....!");
return false;
}
}
Example 4: html form validation
<form action="">
<label for="name">Username</label>
<input id="name" type="text" required />
<label for="Email">Email</label>
<input id="Email" type="text" required />
</form>