Need help testing a POST variable

[vincej]

HI - I'm trying to write an expression which tests the existence of a value within a POST variable. I have tried every which way ie isset, empty, ==0.00, NULL and yet I'm doing something wrong as nothing works. I hope you can help this student of PHP !  The expression is testing whether a price per lb exists ie the price of chicken per pound. But some products are not priced this way eg a jar of jam has no $pricelb[$i].  Here's some detail. The expression I am testing is:

 

if (!isset($pricelb[$i])){           // FIRST HALF FAILS 
$ordervalue =  $price[$i];
$weight = '0.00';}
else	                                      // SECOND HALF WORKS 
$pricelb = $pricelb[$i];{
$weight = $weight[$i];  
$ordervalue = $pricelb * $weight;

 

 

 

The $pricelb[$i] refers to an array of product weights coming off of the array $pricelb =  $_POST['pricelb'] which I then cycle through using a for Loop, hence $pricelb[$i].

 

Bottom  Line: if there is no pricelb then the then the ordervalue for the purchase is the same as the starting unit price.

 

Suppose I have 2 products on the order. One with a pricelb of 5 and one with none. Then I do print_r on $_POST['pricelb'] I get:

Array ( [0] => 5 )

  I.E. the second value is absent. YET, if I look into the DB table I see pricelb 0.00 for the second value  - very confusing !

 

 

MANY MANY thanks ! for all  your help !

 

 

 

 

 

 

[Jessica]

This can't be your actual code, it has significant syntax errors.

 

Before this code, add print_r($pricelb); and see what you get.

[vincej]

Hi  jesirose

 

Once again your helpig me out - thanks !

 

here;'s the array :

 

Post Weight lb

Array ( [0] => 5.00 [1] => 0.00 ) 

 

[vincej]

I have tried testing for 0.00 - maybe I did something wrong in the syntax ...

[Jessica]

Try if it's > 0. PHP will convert it for you,

[vincej]

Not sure why I would check if it;'s greater than 0.  I'm checking to see if it is zero or empty. I'll try == 0 

[Jessica]

It looks like you're doing an if else. If it's 0 do one thing, otherwise do another. The same logic applies if you want to do if it's not 0, do that other thing, otherwise do that first one.

[MMDE]

This might be interesting to take a look at as well:

http://www.php.net/manual/en/types.comparisons.php

 

And this:

http://www.php.net/manual/en/language.operators.comparison.php

[vincej]

Ok - I get it, so I flipped the logic around the other way and I now get succes where I had failure and failure where i had success

 

 

for ($i = 0; $i < $numloops ; $i++) {

if ($pricelb[$i] < 0 ){
$pricelb = $pricelb[$i];
$weight = $weight[$i];  
$ordervalue = $pricelb * $weight;}
else
$ordervalue =  $price[$i];

 

 

When I echo the outputs of this I get:

 

 

line 214   Expected Price Array ( [0] => 60.00 [1] => 15.00 )
line 215  PriceLB 5.00
line 216  Weight 5
line 217 OrderValue 60.00
line 218  ProdID 17
line 219  Order ID JAC8846

//********************************************//

line 214   Expected Price Array ( [0] => 60.00 [1] => 15.00 )
line 215  PriceLB 0.00
line 216  Weight 
A PHP Error was encountered

Severity: Notice

Message: Undefined offset: 1

Filename: models/mpos.php

Line Number: 225

line 217 OrderValue 15.00
line 218  ProdID 28
line 219  Order ID JAC8846

 

 

I'm not surprised that I get an offset error on the second pass as now the variable will be empty for $pricelb[$i]

 

 

 

Thanks for sticking with this !

[vincej]

I must hallucinating ! .. I'm looking at the DB table and it appears to be working.

 

Let me triple check !

[vincej]

Nope false hope --- Now when there is a Pricelb present the expression which calculates order value is failing.

[Jessica]

Your code says if the price per lb at $i is less than 0, the price is the price per lb at $i.

Is that what you want it to say?

[vincej]

OOPS .. finger trouble should  have been > 0 !  AND IT NOW WORKS !!

 

Weird thing though - how flipping the logic caused it to work whilst, testing for if ($pricelb[$i] == 0 ) or NULL  should fail. I suppose that  the >0 expression is less specific and therefore has a better chance of passing ??

 

MANY MANY Thanks you are a super star !

 

Have a good weekend - till next time !