Form Field Validation

[Anon]

I have been looking for a form field validator that isnt using the javascript alert thing.
I`ve tried a few and havent found one I really like.. And this is for a multi page form so I cant use PHP_SELF. I would like to check the form field on submit.. Any Ideas?

Checkboxes too 🙂

Thanks in advance

[Anon]

Here is a simple example.
when the user submits the form data to your next/processing script, this will alert the user.

if ($First_Name == "") {
echo "b>Your Name is incomplete</B>. Please go back and enter your First Name.";
exit;
}

Hope this helps.
Peter

[Anon]

Thank You sooo much !!! I love the "exit" tag... cuts the rest of the page off looks great !! Lots I can do with this one...

[Anon]

It worked, But how can I add additional variables to the IF statement?

I tried a few
This is the IF statement.

if ($months_to_receive_newsletters == "") {

Thanks

[Anon]

Since the current woeful state of HTML Forms does not support anything like VC++ or Visual Basic's input masking, here are three functions I wrote out of necessity for dealing with user phone numbers. But I think the principles can be used for many text box inputs. Just cook them a bit and you get the idea :-)

Please note: what follows is pretty basic material. My point is not to be a bore, but only to instruct those that may not be aware of PHP's capibilities (which I myself am still learning).

Basically, when checking phone numbers that are input from the user, I first "strip" them of all extraneous characters:

/* -----------------------------------------------------------------

Strip the given phone number of anything that is not a number,
e.g., ( ) - [spaces] etc.

--------------------------------------------------------------- */

function StripPhoneNum($phone_num)
{
$len = strlen($phone_num); // assume "[phone]"

for ($i = 0; $i < $len; $i++) // munch thru phone num
{

$a =  $phone_num[$i];

if ( ($a < "0") || ($a > "9") )    // if not a number, delete char
  $striped_phone_num .= "";
else
  $striped_phone_num .= $phone_num[$i];

}

return $striped_phone_num;

}

. . . Next I check the stripped phone number for validity :

/* -----------------------------------------------------------------

Check the given "stripped" phone number for validity.
If Ok, return -1. Otherwise, return the phone number (bad) length.

--------------------------------------------------------------- */

function CheckPhoneNum($phone_num)
{
$len = strlen($phone_num);

if ($len != 10) // e.g. "4128630000"
return $len;
else
return -1;
}

. . . At this point, you could warn your user with an error message, something like

<? echo "Bad phone number $phone_num detected. Please re-enter!"; ?>

. . . Finally, when I want to restore what the user is accustomed to looking
at, I call this function :

/* -----------------------------------------------------------------

Restore dashes to valid (10 digit) phone number
Check to make sure number is valid first.

--------------------------------------------------------------- */

function ReformatPhoneNum($phone_num)
{

$len = CheckPhoneNum($phone_num);

if ($len != -1)
return $phone_num;

$len = strlen($phone_num);

for ($i = 0; $i < $len; $i++)
{
$formatted_phone_num .= $phone_num[$i];
if ( ($i == 2) || ($i == 5) )
$formatted_phone_num .= "-"; // append the dash char
}

return trim($formatted_phone_num);

}

So the striped "4128630000" reappears as ""412-863-0000" which is much more pleasing to the eyes. True, the original "(412)" is now "412-" but that's not too bad to look at considering.

I don't mean to preach here, but too many software weenies out there seem to forget that the customer is king. So don't let a little bit of programming get in the way of treating them just like that. Otherwise, they may not come back to your website and all of the above would be elementary :-)

Comments on my "primitive" style of coding are welcomed!

[Anon]

You can add additional variables to the IF statement. Adding as many if statements as needed is less confusing.

if ($First_Name == "") {
echo "your message";
exit;
}

if ($Last_Name == "") {
echo "your message";
exit;
}

or you can also do:
// declare your variables/messages at the top of the script

$error1 = "Please go back and enter your first name<br>";
$error2 = "Please go back and enter your last name<br>";

if ($First_Name == "" Or $First_Name == " ") {
echo "$error1";
exit; }
if ($Last_Name == "" Or $Last_Name == " ") {
echo "$error2";
exit; }

the == " " will prevent a user from entering white space.

[kelkar_mandar]

//set a var to null initially]
$error='';

if ($name==''){
$error.="Name, ";
} elseif ($address==''){
$error.="Address, ";
}

//and number of fields you want

//i know u say $error gives a , at end
//remove it this way
$error=substr($error,0,strlen($error-2));

//in the end say
if (!empty($error)){
echo "$error ,has been left blank";
} else {
echo "what ever you want here";
}

this definately works

cheers :-)
[e-mail]

[Anon]

That's a good suggestion. If you want to get even more helpful to the user, you can highlight any field titles where the values are incorrect. This is a nice adjunct to just telling them in an error message what's wrong.

My favorite way of doing this is to create an array, and then add the desired color value to an element named after the field if it's incorrect:

$error_colors = array();

...

if ($last_name == '')
&nbsp;&nbsp;$error_colors[last_name] = 'color="#ff0000"';

...

Then, in the part where the form is displayed, you say:

echo '&lt;td&gt;&lt;font ' . $error_colors[last_name] '&gt;';
echo 'Last Name:&lt;/font&gt;&lt;/td&gt;';

[Anon]

Thanks to all of you guys... Now I have to try all of the techniques !! I learned a lot and I`ll let you know which I decided on