Some days back I had posted " Perfect Javascript Form Validation using RegularExpressions ", one of the reader commented like this "If I disable Javascript?". So in this post I given a simple example about "Server Side Form Validation using Regular Expressions ". Take a look at live demo.

Download Script
Live Demovalidation.php
Contains PHP code. eregi — Case insensitive regular expression match.
<?php
if($_POST){
$name = $_POST['name'];
$email = $_POST['email'];
$username = $_POST['username'];
$password = $_POST['password'];
$gender = $_POST['gender'];
// Full Name
if (eregi('^[A-Za-z0-9 ]{3,20}$',$name)){
$valid_name=$name;
}
else
{
$error_name='Enter valid Name.';
}
// Email
if (eregi('^[a-zA-Z0-9._-]+@[a-zA-Z0-9._-]+\.([a-zA-Z]{2,4})$', $email)){
$valid_email=$email;
}
else
{
$error_email='Enter valid Email.';
}
// Usename min 2 char max 20 char
if (eregi('^[A-Za-z0-9_]{3,20}$',$username)){
$valid_username=$username;
}
else
{
$error_username='Enter valid Username min 3 Chars.';
}
// Password min 6 char max 20 char
if (eregi('^[A-Za-z0-9!@#$%^&*()_]{6,20}$',$password)){
$valid_password=$password;
}
else
{
$error_password='Enter valid Password min 6 Chars.';
}
// Gender
if ($gender==0){
$error_gender='Select Gender';
}
else
{
$valid_gender=$gender;
}
if((strlen($valid_name)>0)&&(strlen($valid_email)>0)
&&(strlen($valid_username)>0)&&(strlen($valid_password)>0) && $valid_gender>0 )
{
mysql_query(" SQL insert statement ");
header("Location: thanks.html");
}
else{ }
}
?>
index.php
Contains HTML code. You have to include validation.php file.
<php include("validation.php"); ?>
<form method="post" action="" name="form">
Full name : <input type="text" name="name" value="<?php echo $valid_name; ?>" />
<?php echo $error_name; ?>
Email : <input type="text" name="name" value="<?php echo $valid_email; ?>" />
<?php echo $error_email; ?>
Username : <input type="text" name="name" value="<?php echo $valid_username; ?>" />
<?php echo $error_username; ?>
Password : <input type="password" name="name" value="<?php echo $valid_password; ?>" />
<?php echo $error_password; ?>
Gender : <select name="gender">
<option value="0">Gender</option>
<option value="1">Male</option>
<option value="2">Female</option>
</select>
<?php echo $error_gender; ?>
</form>
<form method="post" action="" name="form">
Full name : <input type="text" name="name" value="<?php echo $valid_name; ?>" />
<?php echo $error_name; ?>
Email : <input type="text" name="name" value="<?php echo $valid_email; ?>" />
<?php echo $error_email; ?>
Username : <input type="text" name="name" value="<?php echo $valid_username; ?>" />
<?php echo $error_username; ?>
Password : <input type="password" name="name" value="<?php echo $valid_password; ?>" />
<?php echo $error_password; ?>
Gender : <select name="gender">
<option value="0">Gender</option>
<option value="1">Male</option>
<option value="2">Female</option>
</select>
<?php echo $error_gender; ?>
</form>
Related posts :
Submit a Form without Refreshing page with jQuery and Ajax.Perfect Javascript Form Validation using RegularExpressions











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if((strlen($valid_name)>0)&&(strlen($valid_email)>0)
&&(strlen($valid_username)>0)&&(strlen($valid_password)>0) && $valid_gender>0 )
{
mysql_query(" SQL insert statement ");
header("Location: thanks.html");
}
else{ }
}
You don't need else {}
its cool, @Srinivass all the credits for you man!, hope more interesting topics will come on this blogger!
Nice article. But u can use preg_match() which is fast.
yes, use preg_match(). It is not only faster, but ereg will probably not be included as standard in future PHP versions
Dude you go way out of your way on this.
put the regexs into an array
$regs['name'] = "..*"; etc....
then loop through the array
foreach( $regs as $k => $v )
then
if( ! ereg( $v , $_POST[$k] ) )
{
$errors[$k] = "Invalid!";
}
use a loop luke!
Also store the error text in another array of string if you want to display text according to the error...
It's nice and clean, but I would suggest to add some lines to keep the gender choice in case of validation not passed.
Thanks for sharing this.
Panamon Rn+
I do believe that it would be more appropriate to use filter functions instead.
Regards,
Márcio
with the name you can't use double barrels carl john-joe for eg