Validate Email
We can perform an email validation through this function.
function isValidEmail($email){
return eregi('^[_a-z0-9-]+(\.[_a-z0-9-]+)*@[a-z0-9-]+(\.[a-z0-9-]+)*(\.[a-z]{2,3})$', $email);
}
After fainted for a few seconds when i saw unreal4u finding, i decided to throw up preg_match solution instead.
function isValidEmail($email){
return preg_match('/^[_a-z0-9-]+(\.[_a-z0-9-]+)*@[a-z0-9-]+(\.[a-z0-9-]+)*(\.[a-z]{2,3})$/i', $email);
}
PHP 5.2 and above.
function fnValidateEmail($email)
{
return filter_var($email, FILTER_VALIDATE_EMAIL);
}
Sanitize Email
We can further sanitize our email to ensure that everything is alright.
function fnSanitizeEmaill($string) {
return preg_replace( '((?:\n|\r|\t|%0A|%0D|%08|%09)+)i' , '', $string );
}
PHP 5.2 and above.
function fnSanitizeEmaill($url)
{
return filter_var($url, FILTER_SANITIZE_EMAIL);
}
Validate Email Exist
This is not possible but certain validation can be use to validate email existence.
function check_email($email)
{
$email_error = false;
$Email = htmlspecialchars(stripslashes(strip_tags(trim($email)))); //parse unnecessary characters to prevent exploits
if ($Email == '') { email_error = true; }
elseif (!eregi('^([a-zA-Z0-9._-])+@([a-zA-Z0-9._-])+\.([a-zA-Z0-9._-])([a-zA-Z0-9._-])+', $Email)) { email_error = true; }
else {
list($Email, $domain) = split('@', $Email, 2);
if (! checkdnsrr($domain, 'MX')) { email_error = true; }
else {
$array = array($Email, $domain);
$Email = implode('@', $array);
}
}
if (email_error) { return false; } else{return true;}
}
Validate Number Only
We can use PHP built-in function to validate whether a given value is a number.
function fnValidateNumber($value)
{
#is_ double($value);
#is_ float($value);
#is_ int($value);
#is_ integer($value);
return is_numeric($value);
}
PHP 5.2 and above.
function fnValidateNumber($value)
{
#return filter_var($value, FILTER_VALIDATE_FLOAT); // float
return filter_var($value, FILTER_VALIDATE_INT); # int
}
Sanitize Number
We can force all value to be only numeric by sanitize them.
function fnSanitizeNumber($str)
{
#letters and space only
return preg_match('/[^0-9]/', '', $str);
}
PHP 5.2 and above.
function fnSanitizeNumber($value)
{
#return filter_var($value, FILTER_SANITIZE_NUMBER_FLOAT); // float
return filter_var($value, FILTER_SANITIZE_NUMBER_INT); # int
}
Validate String Only
Sometimes to validate name we can use this function to restrict only letters and spaces.
function fnValidateStringr($str)
{
#letters and space only
return preg_match('/^[A-Za-z\s ]+$/', $str);
}
Sanitize String
We can sanitize it instead of validate user input.
function fnSanitizeStringr($str)
{
#letters and space only
return preg_replace('/[^A-Za-z\s ]/', '', $str);
}
PHP 5.2 and above. built-in function by PHP provides a much more powerful sanitize capability.
function fnSanitizeStringr($str)
{
return filter_var($str, FILTER_SANITIZE_STRIPPED); # only 'String' is allowed eg. '<br>HELLO</br>' => 'HELLO'
}
Validate Alphanumeric Characters
This validates alphanumeric characters.
function fnValidateAlphanumeric($string)
{
return ctype_alnum ($string);
}
Sanitize Alphanumeric Characters
This sanitize alphanumeric characters. eg. “HELLO! Do we have 90 idiots running around here?” => “HELLO Do we have 90 idiots running around here”
function fnSanitizeAlphanumeric($string)
{
return preg_replace('/[^a-zA-Z0-9]/', '', $string);
}
Validate URL Exist
This function will check whether a given URL exist and not only validate it.
function url_exist($url)
{
$url = @parse_url($url);
if (!$url)
{
return false;
}
$url = array_map('trim', $url);
$url['port'] = (!isset($url['port'])) ? 80 : (int)$url['port'];
$path = (isset($url['path'])) ? $url['path'] : '';
if ($path == '')
{
$path = '/';
}
$path .= (isset($url['query'])) ? '?$url[query]' : '';
if (isset($url['host']) AND $url['host'] != @gethostbyname($url['host']))
{
if (PHP_VERSION >= 5)
{
$headers = @get_headers('$url[scheme]://$url[host]:$url[port]$path');
}
else
{
$fp = fsockopen($url['host'], $url['port'], $errno, $errstr, 30);
if (!$fp)
{
return false;
}
fputs($fp, 'HEAD $path HTTP/1.1\r\nHost: $url[host]\r\n\r\n');
$headers = fread($fp, 4096);
fclose($fp);
}
$headers = (is_array($headers)) ? implode('\n', $headers) : $headers;
return (bool)preg_match('#^HTTP/.*\s+[(200|301|302)]+\s#i', $headers);
}
return false;
}
Validate URL Format
This function will validate a given url to ensure the format is correct.
function fnValidateUrl($url){
return preg_match('/^(http(s?):\/\/|ftp:\/\/{1})((\w+\.){1,})\w{2,}$/i', $url);
}
PHP 5.2 and above.
function fnValidateUrl($url)
{
return filter_var($url, FILTER_VALIDATE_URL);
}
Sanitize URL
PHP 5.2 and above.
function fnSanitizeUrl($url)
{
return filter_var($url, FILTER_SANITIZE_URL);
}
Validate Image Exist
This function will check whether a given image link exist and not only validate it.
function image_exist($url) {
if(@file_get_contents($url,0,NULL,0,1)){return 1;}else{ return 0;}
}
Validate IP Address
This function will validate an IP address.
function fnValidateIP($IP){
return preg_match('/^(([1-9]?[0-9]|1[0-9]{2}|2[0-4][0-9]|25[0-5]).){3}([1-9]?[0-9]|1[0-9]{2}|2[0-4][0-9]|25[0-5])$/',$IP)
}
PHP 5 and above. This can also specific validation for IPV4 or IPV6.
function fnValidateIP($ip)
{
return filter_var($ip, FILTER_VALIDATE_IP);
}
Validate Proxy
This function will let us detect proxy visitors even those that are behind anonymous proxy.
function fnValidateProxy(){
if ($_SERVER['HTTP_X_FORWARDED_FOR']
|| $_SERVER['HTTP_X_FORWARDED']
|| $_SERVER['HTTP_FORWARDED_FOR']
|| $_SERVER['HTTP_VIA']
|| in_array($_SERVER['REMOTE_PORT'], array(8080,80,6588,8000,3128,553,554))
|| @fsockopen($_SERVER['REMOTE_ADDR'], 80, $errno, $errstr, 30))
{
exit('Proxy detected');
}
}
Validate Username
Before we validate whether a given username is matches the one in our database, we can perform a validation check first to prevent any unnecessary SQL call.
function fnValidateUsername($username){
#alphabet, digit, @, _ and . are allow. Minimum 6 character. Maximum 50 characters (email address may be more)
return preg_match('/^[a-zA-Z\d_@.]{6,50}$/i', $username);
}
Validate Strong Password
Another good thing is to validate whether a particular password given by the user is strong enough. You can do that using this function which required the password to have a minimum of 8 characters, at least 1 uppercase, 1 lowercase and 1 number.
function fnValidatePassword($password){
#must contain 8 characters, 1 uppercase, 1 lowercase and 1 number
return preg_match('/^(?=^.{8,}$)((?=.*[A-Za-z0-9])(?=.*[A-Z])(?=.*[a-z]))^.*$/', $password);
}
Validate US Phone Number
This function will validate US phone number for US users.
function fnValidateUSPhone($phoneNo){
return preg_match('/\(?\d{3}\)?[-\s.]?\d{3}[-\s.]\d{4}/x', $phoneNo);
}
Validate US Postal Code
This function validate US postal code.
function fnValidateUSPostal($postalcode){
#eg. 92345-3214
return preg_match('/^([0-9]{5})(-[0-9]{4})?$/i',$postalcode);
}
Validate US Social Security Numbers
This function validate US Social Security Numbers.
function fnValidateUSSocialSecurityCode($ssb){
#eg. 531-63-5334
return preg_match('/^[\d]{3}-[\d]{2}-[\d]{4}$/',$ssn);
}
Validate Credit Card
This function validate credit card format.
function fnValidateCreditCard($cc){
#eg. 718486746312031
return preg_match('/^(?:4[0-9]{12}(?:[0-9]{3})?|5[1-5][0-9]{14}|6011[0-9]{12}|3(?:0[0-5]|[68][0-9])[0-9]{11}|3[47][0-9]{13})$/', $cc);
}
Validate Date
This is a date format MM-DD-YYYY or MM-DD-YY validation which validate from year 0000-9999.
function fnValidateDate($date){
#05/12/2109
#05-12-0009
#05.12.9909
#05.12.99
return preg_match('/^((0?[1-9]|1[012])[- /.](0?[1-9]|[12][0-9]|3[01])[- /.][0-9]?[0-9]?[0-9]{2})*$/', $date);
}
This is a date format YYYY-DD-MM or YY-MM-DD validation which validate from year 0000-9999.
function fnValidateDate($date){
#2009/12/11
#2009-12-11
#2009.12.11
#09.12.11
return preg_match('#^([0-9]?[0-9]?[0-9]{2}[- /.](0?[1-9]|1[012])[- /.](0?[1-9]|[12][0-9]|3[01]))*$#'', $date);
}
Validate Hexadecimal Colors
This is a good validation for people who allows their user to change color in their system.
function fnValidateColor($color){
#CCC
#CCCCC
#FFFFF
return preg_match('/^#(?:(?:[a-f0-9]{3}){1,2})$/i', $color);
}
Make Query Safe
This function help sanitize our data to be SQL injection safe.
function _clean($str){
return is_array($str) ? array_map('_clean', $str) : str_replace('\\', '\\\\', htmlspecialchars((get_magic_quotes_gpc() ? stripslashes($str) : $str), ENT_QUOTES));
}
//usage call it somewhere in beginning of your script
_clean($_POST);
_clean($_GET);
_clean($_REQUEST);// and so on..
Make Data Safe
This function help to keep us protected against XSS, JS and SQL injection by removing tags.
function _clean($str){
return is_array($str) ? array_map('_clean', $str) : str_replace('\\', '\\\\', strip_tags(trim(htmlspecialchars((get_magic_quotes_gpc() ? stripslashes($str) : $str), ENT_QUOTES))));
}
//usage call it somewhere in beginning of your script
_clean($_POST);
_clean($_GET);
_clean($_REQUEST);// and so on..
