Re: Is there limitation for switch case: argument's value?

2009/8/22 Keith <survivor_bus@hotmail.com>: > Thanks! Torben. > I got the point now and it works! :-) > I'm doing this because the statements of each cases is quite long, and I > wish to have minimum coding without repetition. Hi Keith, Glad it works! I'm not sure how inverting the case statement helps you minimize the code in each case. As both I and Adam showed, you can do the same thing more efficiently (and IMHO much more readably) like this: switch ($sum) { case 8: break; case 7: case 6: break; case 2: case 1: break; case 0: break; default: break; } > "Lars Torben Wilson" <larstorben@gmail.com> wrote in message > > news:36d4833b0908202323p3c858b5fn6a1d6775aa7f8997@mail.gmail.com... >> >> 2009/8/20 Keith <survivor_bus@hotmail.com>: >>> >>> Hi, >>> I encounter a funny limitation here with switch case as below: >>> The value for $sum is worked as expected for 1 to 8, but not for 0. >>> When the $sum=0, the first case will be return, which is "sum=8". >>> Is there any limitation / rules for switch case? Thanks for advice! >>> >>> Keith >> >> Hi Keith, >> >> Try replacing 'switch($sum)' with 'switch(true)'. >> >> Note that unless you have very good reasons for using a switch >> statement like this, and know exactly why you're doing it, it's often >> better just to use it in the normal fashion. i.e.: >> >>      switch ($sum) >>       { >>       case 8: >>           break; >>       case 7: >>       case 6: >>           break; >>       case 2: >>       case 1: >>           break; >>       case 0: >>           break; >> default: >>           break; >>       } >> >> Some people like the syntax you've presented but honestly, there's >> usually a better way to do it. >> >> This is also somewhat faster too, although you may only notice the >> difference in very tight loops where you're counting every nanosecond. >> >> >> Regards, >> >> Torben >> >>> $sum=0; >>> switch($sum) >>> { >>>  case ($sum==8): >>>  echo "sum=8"; >>>  break; >>>      case ($sum==7 || $sum==6): >>>      echo "sum=7 or 6"; >>>      break; >>>  case ($sum==2 || $sum==1): >>>  echo "sum=2 or 1"; >>>  break; >>>      case 0: >>>      echo "sum=0"; >>>      break; >>>  default: >>>  echo "sum=3/4/5"; >>>  break; >>> } >>> -- >>> PHP General Mailing List (http://www.php.net/) >>> To unsubscribe, visit: http://www.php.net/unsub.php >>> >>> > > -- > PHP General Mailing List (http://www.php.net/) > To unsubscribe, visit: http://www.php.net/unsub.php > >