switch statement not working

[Goose87]

Hey everyone,

 

I have the following switch function.  It should take the value, and if its below 10, the person gets 10 quantity, and for every 10 above that, the quantity goes down by 1.

 

The problem I have is that when the value is 0, the quantity gained goes for the quantity 9 one.  I cant explain why it isnt working.

 

switch($value){
case($value<11 OR $value==0):
$quantity=10;
break;
case($value>=11 AND $value<20):
$quantity=9;
break;
case($value>=20 AND $value<30):
$quantity=8;
break;
case($value>=30 AND $value<40):
$quantity=7;
break;
case($value>=40 AND $value<50):
$quantity=6;
break;
case($value>=50 AND $value<60):
$quantity=5;
break;
case($value>=60 AND $value<70):
$quantity=4;
break;
case($value>=70 AND $value<80):
$quantity=3;
break;
case($value>=80 AND $value<90):
$quantity=2;
break;
case($value>=90 AND $value<100):
$quantity=1;
break;
case 100:
$quantity=0;
break;
}

I've tried having no brackets, ive tried just $value<11.  I've tried everything, but when $value is 0 it always gives a quantity of 9.

 

Any ideas??

 

Thanks.

[rhodesa]

I don't think you can use AND and OR in the cases. You can just use IF/ELSEIF/ELSE:

 

<?php
if($value >= 100)
  $quantity=0;
elseif($value >= 90)
  $quantity = 1;
elseif($value >= 80)
  $quantity = 2;
elseif($value >= 70)
  $quantity = 3;
elseif($value >= 60)
  $quantity = 4;
elseif($value >= 50)
  $quantity = 5;
elseif($value >= 40)
  $quantity = 6;
elseif($value >= 30)
  $quantity = 7;
elseif($value >= 20)
  $quantity = 8;
elseif($value >= 10)
  $quantity = 9;
else
  $quantity = 10;
?>

 

Or, better yet, turn it into a formula:

<?php
  $quantity = 10 - ($value / 10);
?>

[Goose87]

Ah, thats a darn good point, just do the formula one i feel really stupid now 

 

Thanks a lot for your help.

[kenrbnsn]

It's perfectly fine to have a condition as a case, you just have to switch on the value "true":

<?php
$value = rand(0,100);
switch (true) {
        case ($value<11):
        case ($value==0):
            $quantity=10;
            break;
        case ($value>=11 && $value<20):
            $quantity=9;
            break;
        case ($value>=20 && $value<30):
            $quantity=8;
            break;
        case ($value>=30 && $value<40):
            $quantity=7;
            break;
        case ($value>=40 && $value<50):
            $quantity=6;
            break;
        case ($value>=50 && $value<60):
            $quantity=5;
            break;
        case ($value>=60 && $value<70):
            $quantity=4;
            break;
        case ($value>=70 && $value<80):
            $quantity=3;
            break;
        case ($value>=80 && $value<90):
            $quantity=2;
            break;
        case ($value>=90 && $value<100):
            $quantity=1;
            break;
        default:
            $quantity=0;
            break;
        }
echo "$value<br>$quantity<br>";
?>

 

Ken

[rhodesa]

ah...interesting...i've never thought of using a switch statement like that

[Goose87]

Thanks for the reply ken, that's really informative.

 

I went down the "formula" route, it added a TINY bit of limitation to boundaries I had to set, but I don't mind.

 

I will definately use that type of switch statement in the future, thanks again