How to put my validation block of codes into Function PHP -

how can put validation codes function? how going return , call it? trying call put them in 1 code , call them in function forms. idea?

here's codes:

function validate(){     $errors = array();     //empty array collect errors       //validation codes (need inside function)            if(empty($_post['email']) , filter_var($email, filter_validate_email) != false)          {              $errors[] = "email cannot blank";          }           if(empty($_post['first_name']))          {              $errors[] = "first name cannot blank";          }             if(empty($_post['last_name']))          {              $errors[] = "last name cannot blank";          }              if(empty($_post['password']))          {              $errors[] = "password cannot blank";          }              if(empty($_post['confirm_password']) , $_post['password'] == $_post['confirm_password'])          {              $errors[] = "please enter matching password";          }                if(empty($_post['confirm_password']) , $_post['password'] == $_post['confirm_password'])          {              $errors[] = "please enter matching password";          }              if(!isset($_post['date']) || strtotime($_post['date']) === false)          {              $errors[] = "birth date cannot blank";          }             if(!empty($errors))          {              //if there errors, assign session variable!              $_session['errors'] = $errors;              //redirect user using header('location: ')              header('location: registration_page.php');          }          else          {               $email = $_post['email'];              $first_name = $_post['first_name'];              $last_name = $_post['last_name'];              $password = $_post['password'];              $birth_date = $_post['date'];               //redirect user next part of site!           } } 

so when call this wont work:

echo validate();  

hope can help. thanks!

so you're saying like:

class validation {      public static function emailfilter($input) {         global $_post;         return empty($_post['email']) , filter_var($input,              filter_validate_email) != false ? "email cannot blank" : false;     } } 

or looking else?

edit 1

okay, how about:

function filter ($input, $type) {     if (!$input or !$type) {         switch ($type) {             case "email":                 // check email                 if (empty($_post['email']) , filter_var($input, filter_validate_email)) {                     return "email cannot blank";                 }                 break;             case "first_name":                 if(empty($_post['first_name']))                 {                     return "first name cannot blank";                 }                 break;             // , on.         }     } } 

you call by:

filter($_post['email'], 'email'); 

so then:

if (!filter($_post['email'], 'email')) {     // email checks out. } else {     $error[] = filter($_post['email'], 'email'); } 

there more elegant solutions available, based on think want.