Introduction

I this article I explain how to validate a registration form using a JavaScript function. The registration form fields are validated using a JavaScript function. In this form I am using textboxes, a dropdown list, a text area and a checkbox for validation from a JavaScript function and using some extra scripting like CSS and HTML for designing the form.

Example

This is a CSS file; save it as "form.css":

h2{

margin-left: 50px;

color: Automatic;

margin-top: 0px;

text-Align: Center;

}

form li

{

list-style: none;

margin-bottom: 5px;

}

form ul li label

{

float: left;

clear: left;

width: 265px;

text-align: right;

margin-right: 10px;

font-family:Arial;

font-size:10px;

}

form ul li input, select, span

{

float: left;

margin-bottom: 10px;

border: 1px solid maroon;

}

form textarea

{

float: left;

width: 250px;

height: 80px;

}

[type="submit"]

{

clear: left;

margin: 20px 0 0 300px;

font-size:10px

}


This is a JavaScript file to be saved as "jsvalidation.js." This file validates using a JavaScript function using field_Id for creating the function. The JavaScript function calls the onblur event.

You can try it for validation, use this code.

function firstfocus()

{

var uid = document.registration.username.focus();

return true;

}

function username_validation(mw,my)

{

var uid = document.registration.username;

var uid_len = uid.value.length;

if (uid_len == 0 || uid_len >= my || uid_len < mw)

{

alert("Please enter username/minimum character "+mw+" to "+my);

uid.focus();

return false;

}

document.registration.passwrd.focus();

return true;

}

function passwrd_validation(mv,my)

{

var passwrd = document.registration.passwrd;

var passwrd_len = passwrd.value.length;

if (passwrd_len == 0 ||passwrd_len >= my || passwrd_len < mv)

{

alert("Please enter Password/minimum password "+mv+" to "+my);

passwrd.focus();

return false;

}

document.registration.username.focus();

return true;

}

function allLetter()

{

var uname = document.registration.username;

var letters = /^[A-Za-z]+$/;

if(uname.value.match(letters))

{

document.registration.address.focus();

return true;

}

else

{

alert('Username only character');

uname.focus();

return false;

}

}

function alphanumeric()

{

var uadd = document.registration.address;

var letters = /^[0-9a-zA-Z]+$/;

if(uadd.value.match(letters))

{

document.registration.country.focus();

return true;

}

else

{

alert('Address only alphanumeric');

uadd.focus();

return false;

}

}

function countryselect()

{

var ucountry = document.registration.country;

if(ucountry.value == "Default")

{

alert('Please select your country');

ucountry.focus();

return false;

}

else

{

document.registration.zip.focus();

return true;

}

}

function allnumeric()

{

var uzip = document.registration.zip;

var numbers = /^[0-9]+$/;

if(uzip.value.match(numbers))

{

document.registration.email.focus();

return true;

}

else

{

alert('ZIP Code only numeric');

uzip.focus();

return false;

}

}

function ValidateEmail()

{

var uemail = document.registration.email;

var mailformat = /^\w+([\.-]?\w+)*@\w+([\.-]?\w+)*(\.\w{2,3})+$/;

if(uemail.value.match(mailformat))

{

document.registration.desc.focus();

return true;

}

else

{

alert("Invalid email address!");

uemail.focus();

return false;

}

}


This is a HTML file; save it as "Registration.php." In this form I used the events Onload, Onblur, Onclick.

<meta charset="utf-8">

<title>Registration Form</title>

<meta name="keywords" content="example, JavaScript Form Validation, Sample registration form" />

<meta name="description" content="This document is an example of JavaScript Field label form validation using a sample registration form. " />

<link rel='stylesheet' href='form.css' type='text/css' />

<script src="jsvalidation.js"></script>

</head>

<body bgcolor="#E7DEDC"onload="firstfocus();">

<h2>Registration Form</h2>

<form name='registration'">

<ul>

<li><label for="username">Username:</label></li>

<li><input type="text" name="username" size="12" onblur="username_validation(6,12)"/></li>

<li><label for="passwrd">Password:</label></li>

<li><input type="password" name="passwrd" size="12" onblur="passwrd_validation(6,12)"/></li>

<li><label for="user">Name:</label></li>

<li><input type="text" name="user" size="37" onblur="allLetter()"/></li>

<li><label for="address">Address:</label></li>

<li><input type="text" name="address" size="37" onblur="alphanumeric()"/></li>

<li><label for="country">Country:</label></li>

<li><select name="country" onblur="countryselect()">

<option selected="" value="Default">(Please select a country)</option>

<option value="AF">Australia</option>

<option value="AL">Canada</option>

<option value="DZ">India</option>

<option value="AS">Russia</option>

<option value="AD">USA</option>

</select></li>

<li><label for="zip">ZIP Code:</label></li>

<li><input type="text" name="zip" size="12" onblur="allnumeric()"/></li>

<li><label for="email">Email:</label></li>

<li><input type="text" name="email" size="37" onblur="ValidateEmail()" /></li>

<li><label id="gender">Sex:</label></li>

<li><input type="radio" name="sex" value="Male" checked /><span>Male</span></li>

<li><input type="radio" name="sex" value="Female" /><span>Female</span></li>

<li><label>Language:</label></li>

<li><input type="checkbox" name="en" value="en" checked /><span>English</span></li>

<li><input type="checkbox" name="nonen" value="noen" /><span>Non English</span></li>

<li><label for="desc">About:</label></li>

<li><textarea name="desc" id="desc" cols"5"></textarea></li>

<li><input type="submit" name="submit" value="Submit" onclick="alert('Form submitted successfully')" /></li>

</ul>

</form>

</body>

Output
Validate registration form.jpg