[RESOLVED] Help with mb_substr function

[mayandy]

Hi

I am building a simple shopping cart and working on the shipping fees. In a previous page, I obtain the customer's address and pass on the value $Postcode through the form. Next, I use the mb_substr function to check the first 4 characters of the postcode. If the value of $postcode1 is SE22, then delivery is free, otherwise I will charge £3. However, the code below doesn't seem to work. Where am I going wrong?

Mayan

// check if eligible for free delivery
$postcode1 = mb_substr($Postcode,0,4);
if($postcode != "SE22"  ){
$delivery = 3;
} else {
$delivery = 0;
}

[paulnaj]

What 'doesn't seem to work'? It's hard to tell from your code.

Having said that ...

1. Turn on error_reporting ... put

   error_reporting(E_ALL);

   at the top the page you are trying to debug. Remove

2. Are you getting the form variables correctly ... you should have something like

   $Postcode = $_POST['postcode'];

   I say 'something like' because I don't know what the name of the form element is.

3. Should this line

   if($postcode != "SE22"  ){

   be

   if($postcode1 != "SE22"  ){

   ?

Paul

[mayandy]

Hi Paul

Checked the code and it seems correct to me. However I am still obtaining the wrong delivery amount.

// check if eligible for free delivery
$Postcode = $_POST['Postcode']; // the value of this variable is SE22 5JP
$postcode1 = mb_substr($Postcode,0,4);
if($postcode1 != "SE22"  ){
$delivery = 3;
} else {
$delivery = 0;
echo $Postcode; // prints SE22 5JP
echo $postcode1 // prints SE22
echo $delivery // prints 3 when it should be 0 
} 

[mayandy]

Sorry, previous post had some syntax errors. This now seems correct to me but not getting the result of 0.

// check if eligible for free delivery
$Postcode = $_POST['Postcode']; // the value of this variable is SE22 5JP
$postcode1 = mb_substr($Postcode,0,4);
if($postcode1 != "SE22"  ){
$delivery = 3;
} else {
$delivery = 0;
} 
echo $Postcode; // prints SE22 5JP
echo $postcode1; // prints SE22
echo $delivery; // prints 3 when it should be 0

[scrupul0us]

erased... OP posted updated while i was typing

[paulnaj]

I haven't used the mb_ string functions before - are you sure it's necessary? If you're not sure then try the standard substr() function instead.

Also, you might try 'trimming' the $POST var just in case extra whitespace is coming along for the ride ...

$Postcode = trim($_POST['Postcode']);

P.

[scrupul0us]

works for me:

$Postcode = 'SE22 5JP'; // the value of this variable is SE22 5JP
$postcode1 = mb_substr($Postcode,0,4);
if($postcode1 != "SE22"  ){
$delivery = 3;
} else {
$delivery = 0;
echo "Postcode: $Postcode<br/>"; // prints SE22 5JP
echo "Substr: $postcode1<br/>"; // prints SE22
echo "Delivery: $delivery"; // prints 0
}

[mayandy]

I was in fact typing in a postcode that had 3 characters then a space, so the trim function fixed the problem. Thanks!