validating multiple fields at once

[drtanz]

hi i have around 40 fields all requiring the same validation, making sure that they are not empty and that they are numeric, can I check them all at once instead of writing a check for each one of them?

[wildteen88]

Use a foreach loop

foreach($_POST as $field_name => $field_value)
{
    if(empty($_POST[$field_name]) || !is_numeric($_POST[$field_name]))
    {
         $error[$field_name] = 'error message here'
     }
}

if(isset($error) && is_array($error))
{
     // display error here
}

[chronister]

Write a function for them, or just do a really long if statement, or you could run them through a foreach loop.

 

There really is no easy way to do it. Long forms are plain tedious.

 

<?php

function checkFields($field)
{
   if(isset($field) && $field != '' & is_numeric($field))
   {
        echo $field.' is not blank and is a number';
   }
   else
   {
      $error .= $field.' did not pass validation';
   }
}

checkFields($_POST['your_field_name']);

?>

 

Nate

 

wildteen88 beat me to the foreach thing...

[GingerRobot]

Use a foreach loop

foreach($_POST as $field_name => $field_value)
{
    if(empty($_POST[$field_name]) || !is_numeric($_POST[$field_name]))
    {
         $error[$field_name] = 'error message here'
     }
}

if(isset($error) && is_array($error))
{
     // display error here
}

 

That does of course assume that you're wanting to check all your posted values. Even if that's the case, you'd need to exclude the submit button from the check:

 

<?php
foreach($_POST as $field_name => $field_value)
{
   if((empty($_POST[$field_name]) || !is_numeric($_POST[$field_name])) && $_POST[$field_name] != 'Submit')//or whatever you called it
   {
        $error[$field_name] = 'error message here'
    }
}

if(isset($error) && is_array($error))
{
    // display error here
}
?>

 

If it's not all of them, then either exclude others or set an array with a list of fields you do want to check --whichever is easiest.

[wildteen88]

That does of course assume that you're wanting to check all your posted values. Even if that's the case, you'd need to exclude the submit button from the check:

good point, forgot about that part.

[drtanz]

yes i need to check all values, so will use the foreach loop excluding the submit thanks alot

[drtanz]

ok so i cant really understand the second if statement, maybe you could explain what happens exactly there. secondly i am including this on the second page to which the first page including the form sends the data. now if there is an error i would like to redirect back to the 1st page after showing an error message, or indeed show it on the 1st page, and also populate the form with the data, how can i do that? thanks

[chronister]

The second statement is to determine if there was an error message set. If $error is set and $error is an array, then display that message.

 

I have found it easier to place the form and it's validation on one page. that way you don't have to worry about sessions to get data between the 2 to display an error message. As it stands, you will probably need to set the error messages in an array and then set that as a session to redirect them back to the page.

 

the header(); function is what you would use to redirect.

 

nate

[drtanz]

How do i place them both the form and the validation on the same page? I could do a submit to self for the validation but then i would still have to submit to another page after for calculation and display of results :S

[chronister]

A quick sample

 

<?php

function contact_form()  // place form in a function
{ 
global $error,$state_list; set some global vars
		if(isset($error)){echo '<div class="error" align="center">'.$error.'</div>';};// if $error is set show it
?>
<form>the form</form>
<?php } // end the function 

if(!$_POST['contact_form'])
{ 
  	// call the contact form function
contact_form();
}
else // else, the form has been submitted so we start processing it
{
// process form
}

?>

 

 

 

 

 

 

 

[chronister]

I forgot to mention that the reason I have the form as a function is because in my form processing I typically will do something like this during the validation before I submit to a db or email or such

 

<?php

if(isset($error))
{
   contact_form();
}
else
{
   //insert to db
   //email the results
   //write to file
   // etc
}
?>

 

This makes it easy to determine where a forms processing is happening... but it makes for lots of code on a page....

 

hope it helps..

 

Nate