Php switch statement - how to manage repeated cases? - php

Question

I'm building a site in which the user should be able to select from three regions where the content should be visible. I have the following regions:
Region 1: Argentina, Uruguay, Paraguay, Chile, Venezuela, Peru
Region 2: Mexico, Colombia, Ecuador, Brazil, Belize, Costa Rica, El
Salvador, Guatemala, Honduras, Nicaragua, Panama
Region 0: It should include all of the countries above
I have the following switch statement:
switch ( $countryCode ) {
case 'AR':
case 'UY':
case 'PY':
case 'CL':
case 'VE':
case 'PR':
// code to execute
break;
case 'MX':
case 'CO':
case 'EC':
case 'BR':
case 'BZ':
case 'CR':
case 'SV':
case 'GT':
case 'HN':
case 'NI':
case 'PA':
// code to execute
break;
case 'AR':
case 'UY':
case 'PY':
case 'CL':
case 'VE':
case 'PR':
case 'MX':
case 'CO':
case 'EC':
case 'BR':
case 'BZ':
case 'CR':
case 'SV':
case 'GT':
case 'HN':
case 'NI':
case 'PA':
// code to execute
break;
default:
// code to execute
break;
}
I'm having trouble with the structure of my switch code, in the part where I have to include all of the countries (Region 0). It seems that I can't repeat countries that have been declared on previous case statements (it's obvious I know), but I can't figure out the right way to do it.
Is there any way to restructure my code so there would be a case statement that includes all of the countries? If it's not posible to do it with a switch, you guys have any other suggestion?
Thank you!

Answer 1

As #KenWhite mentioned, group by region, then check against regions.
Your code could look something like this:
<?php
$regions = [false, false, false];
switch ( $countryCode ) {
case 'AR':
case 'UY':
case 'PY':
case 'CL':
case 'VE':
case 'PR':
$regions[0] = $regions[1] = true;
break;
case 'MX':
case 'CO':
case 'EC':
case 'BR':
case 'BZ':
case 'CR':
case 'SV':
case 'GT':
case 'HN':
case 'NI':
case 'PA':
$regions[0] = $regions[2] = true;
break;
default:
break;
}
if($regions[0]) {
//some code here
}
// etc.

Answer 2

If I understand the question, you have two mutually exclusive code paths and one inclusive one. I would move away from using switch and use sets (i.e. PHP arrays).
$region1 = array_combine(['AR','UY','PY','CL','VE','PR'],true);
$region2 = array_combine(['MX','CO','EC','BR','BZ','CR','SV',
'GT','HN','NI','PA',],true);
if (isset($region1[$countryCode])) {
// Region 1 specific...
}
else if (isset($region2[$countryCode])) {
// Region 2 specific...
}
if (isset($region1[$countryCode],$region2[$countryCode])) {
// Region 0 specific...
}
else {
// Default case...
}
Better yet (if possible) move the code paths to their own functions:
function region1() { }
function region2() { }
function region0() { }
$region1 = array_combine(['AR','UY','PY','CL','VE','PR'],true);
$region2 = array_combine(['MX','CO','EC','BR','BZ','CR','SV',
'GT','HN','NI','PA',],true);
if (isset($region1[$countryCode])) {
region1();
region0();
}
else if (isset($region2[$countryCode])) {
region2();
region0();
}
else {
// Default case...
}

Answer 3

Options A) hard code your scenario (bad idea)
function get_region($country_code){
switch ( $country_code ) {
case 'AR':
case 'UY':
case 'PY':
case 'CL':
case 'VE':
case 'PR':
return 1;
break;
case 'MX':
case 'CO':
case 'EC':
case 'BR':
case 'BZ':
case 'CR':
case 'SV':
case 'GT':
case 'HN':
case 'NI':
case 'PA':
return 2;
break;
default:
return 0;
break;
}
}
echo get_region("AR")."\n";
echo get_region("MX")."\n";
Option B) use external .ini files
regions.ini
; region 1
[1]
country[] = "AR"
country[] = "UY"
country[] = "PY"
country[] = "CL"
country[] = "VE"
country[] = "PE"
; region 2
[2]
country[] = "MX"
country[] = "CO"
country[] = "EC"
country[] = "BR"
country[] = "BZ"
country[] = "CR"
country[] = "SV"
country[] = "GT"
country[] = "HN"
country[] = "NI"
country[] = "PA"
function.php:
function get_region($country_code){
$region = parse_ini_file("regions.ini", true);
if (in_array($country_code,$region[1]['country'], false)){
return 1;
} elseif (in_array($country_code,$region[2]['country'], false)){
return 2;
} else {
return 0;
}
}
echo get_region("AR")."\n";
echo get_region("MX")."\n";